Monday, November 30, 2020

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2492

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2492

Circuit/System Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted to the accelerator pedal

assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to pedal position. The engine control module

(ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.

Conditions for Running the DTC

P2120, P2122, P2123, P2125, P2127, P2128

* DTC P0641 or P0651 is not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2120, P2122, P2123, P2125, P2127, P2128 run continuously when the above conditions are met.

P2138

* DTC P0641, P0651, P2120, P2125 are not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2138 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2120

The APP sensor 1 voltage is less than 0.46 V or greater than 4.7 V for greater than 0.2 s.

P2122

The ECM detects that the APP sensor 1 voltage is less than 0.46 V for greater than 0.2 s.

P2123

The ECM detects that the APP sensor 1 voltage is greater than 4.75 V for greater than 0.2 s.

P2125

The APP sensor 2 voltage is less than 0.32 V or greater than 2.6 V for greater than 0.2 s.

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2491

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2491

* Accelerator Pedal Position Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Accelerator Pedal Position

Sensor/Service and Repair)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement,

programming, and setup

P2127

DTC P2120, P2122, P2123, P2125, P2127, P2128, or P2138

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provide an overview of each diagnostic category.

DTC Descriptors

DTC P2120

- Accelerator Pedal Position (APP) Sensor 1 Circuit

DTC P2122

- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

DTC P2125

- Accelerator Pedal Position (APP) Sensor 2 Circuit

DTC P2127

- Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

- Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

- Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Diagnostic Fault Information

Typical Scan Tool Data

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2490

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2490

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0641 or P0651 are not set.

瀚慖f a DTC is set, refer to DTC P0641 or P0651 (ECM) (See: P Code Charts/P0641) for further diagnosis.

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.32-4.75 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

5. Observe the scan tool APP sensor 1 and 2 parameter. The scan tool should display Agree.

6. Clear the DTCs with the scan tool. Operate the vehicle within the Conditions for Running the DTC or within the conditions that you observed

from the Freeze Frame/Failure Records.

7. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P2120 or P2125 are not the only APP sensor DTCs set.

瀚慖f DTC P2120 or P2125 are the only DTCs set, replace the ECM.

8. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the accelerator pedal.

2. Ignition OFF for 1 minute, test for less than 5 ohm between the appropriate low reference circuit terminal listed below and ground.

* APP sensor 1 terminal F or 4

* APP sensor 2 terminal A or 5

瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace

the ECM.

3. Ignition ON, test for 4.8-5.2 V between the appropriate 5 V reference circuit terminal listed below and ground.

* APP sensor 1 terminal D or 2

* APP sensor 2 terminal C or 1

瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or open/high resistance. If the circuit/connections test

normal, replace the ECM.

瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit/connections test normal, replace the

ECM.

4. Observe the scan tool APP sensor 1 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal E or 3 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

5. Observe the scan tool APP sensor 2 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal B or 6 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

6. Connect a 3 A fused jumper wire between the APP sensor 1 signal circuit terminal E or 3 and the 5 V reference circuit terminal C or 1. Verify

the APP sensor 1 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

7. Connect a 3 A fused jumper wire between the APP sensor 2 signal circuit terminal B or 6 and the 5 V reference circuit terminal C or 1.

Verify the APP sensor 2 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

8. If all circuits/connections test normal, test or replace the Accelerator Pedal Assembly.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2489

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2489

P2122

The ECM detects that the APP sensor 1 voltage is less than 0.46 V for greater than 0.2 s.

P2123

The ECM detects that the APP sensor 1 voltage is greater than 4.75 V for greater than 0.2 s.

P2125

The APP sensor 2 voltage is less than 0.32 V or greater than 2.6 V for greater than 0.2 s.

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2488

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2488

DTC P2125

- Accelerator Pedal Position (APP) Sensor 2 Circuit

DTC P2127

- Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

- Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

- Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Diagnostic Fault Information

Typical Scan Tool Data

Circuit/System Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted to the accelerator pedal

assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to pedal position. The engine control module

(ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.

Conditions for Running the DTC

P2120, P2122, P2123, P2125, P2127, P2128

* DTC P0641 or P0651 is not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2120, P2122, P2123, P2125, P2127, P2128 run continuously when the above conditions are met.

P2138

* DTC P0641, P0651, P2120, P2125 are not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2138 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2120

The APP sensor 1 voltage is less than 0.46 V or greater than 4.7 V for greater than 0.2 s.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2487

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2487

瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace

the ECM.

3. Ignition ON, test for 4.8-5.2 V between the appropriate 5 V reference circuit terminal listed below and ground.

* APP sensor 1 terminal D or 2

* APP sensor 2 terminal C or 1

瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or open/high resistance. If the circuit/connections test

normal, replace the ECM.

瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit/connections test normal, replace the

ECM.

4. Observe the scan tool APP sensor 1 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal E or 3 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

5. Observe the scan tool APP sensor 2 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal B or 6 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

6. Connect a 3 A fused jumper wire between the APP sensor 1 signal circuit terminal E or 3 and the 5 V reference circuit terminal C or 1. Verify

the APP sensor 1 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

7. Connect a 3 A fused jumper wire between the APP sensor 2 signal circuit terminal B or 6 and the 5 V reference circuit terminal C or 1.

Verify the APP sensor 2 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

8. If all circuits/connections test normal, test or replace the Accelerator Pedal Assembly.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.

* Accelerator Pedal Position Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Accelerator Pedal Position

Sensor/Service and Repair)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement,

programming, and setup

P2125

DTC P2120, P2122, P2123, P2125, P2127, P2128, or P2138

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provide an overview of each diagnostic category.

DTC Descriptors

DTC P2120

- Accelerator Pedal Position (APP) Sensor 1 Circuit

DTC P2122

- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

89 Dakota 3.9L: does power steering and brakes run off the same hydraulic circuit?

Lost power steering and brakes on steep hill under under 30mph, was back to normal after shutting off than back on. Truck was running all morning & temps dropped below 35F night before. 89 Dakota 3.9L: does power steering and brakes run off the same hydraulic circuit?
Lost power steering and brakes on steep hill under under 30mph, was back to normal after shutting off than back on. Truck was running all morning & temps dropped below 35F night before.

89 Dakota 3.9L: does power steering and brakes run off the same hydraulic circuit?
Tue, 01 Dec 2020 01:42:16 +0000
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2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2486

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2486

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0641 or P0651 are not set.

瀚慖f a DTC is set, refer to DTC P0641 or P0651 (ECM) (See: P Code Charts/P0641) for further diagnosis.

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.32-4.75 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

5. Observe the scan tool APP sensor 1 and 2 parameter. The scan tool should display Agree.

6. Clear the DTCs with the scan tool. Operate the vehicle within the Conditions for Running the DTC or within the conditions that you observed

from the Freeze Frame/Failure Records.

7. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P2120 or P2125 are not the only APP sensor DTCs set.

瀚慖f DTC P2120 or P2125 are the only DTCs set, replace the ECM.

8. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the accelerator pedal.

2. Ignition OFF for 1 minute, test for less than 5 ohm between the appropriate low reference circuit terminal listed below and ground.

* APP sensor 1 terminal F or 4

* APP sensor 2 terminal A or 5

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2485

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2485

Circuit/System Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted to the accelerator pedal

assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to pedal position. The engine control module

(ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.

Conditions for Running the DTC

P2120, P2122, P2123, P2125, P2127, P2128

* DTC P0641 or P0651 is not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2120, P2122, P2123, P2125, P2127, P2128 run continuously when the above conditions are met.

P2138

* DTC P0641, P0651, P2120, P2125 are not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2138 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2120

The APP sensor 1 voltage is less than 0.46 V or greater than 4.7 V for greater than 0.2 s.

P2122

The ECM detects that the APP sensor 1 voltage is less than 0.46 V for greater than 0.2 s.

P2123

The ECM detects that the APP sensor 1 voltage is greater than 4.75 V for greater than 0.2 s.

P2125

The APP sensor 2 voltage is less than 0.32 V or greater than 2.6 V for greater than 0.2 s.

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2484

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2484

* Accelerator Pedal Position Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Accelerator Pedal Position

Sensor/Service and Repair)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement,

programming, and setup

P2123

DTC P2120, P2122, P2123, P2125, P2127, P2128, or P2138

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provide an overview of each diagnostic category.

DTC Descriptors

DTC P2120

- Accelerator Pedal Position (APP) Sensor 1 Circuit

DTC P2122

- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

DTC P2125

- Accelerator Pedal Position (APP) Sensor 2 Circuit

DTC P2127

- Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

- Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

- Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Diagnostic Fault Information

Typical Scan Tool Data

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2483

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2483

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0641 or P0651 are not set.

瀚慖f a DTC is set, refer to DTC P0641 or P0651 (ECM) (See: P Code Charts/P0641) for further diagnosis.

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.32-4.75 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

5. Observe the scan tool APP sensor 1 and 2 parameter. The scan tool should display Agree.

6. Clear the DTCs with the scan tool. Operate the vehicle within the Conditions for Running the DTC or within the conditions that you observed

from the Freeze Frame/Failure Records.

7. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P2120 or P2125 are not the only APP sensor DTCs set.

瀚慖f DTC P2120 or P2125 are the only DTCs set, replace the ECM.

8. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the accelerator pedal.

2. Ignition OFF for 1 minute, test for less than 5 ohm between the appropriate low reference circuit terminal listed below and ground.

* APP sensor 1 terminal F or 4

* APP sensor 2 terminal A or 5

瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace

the ECM.

3. Ignition ON, test for 4.8-5.2 V between the appropriate 5 V reference circuit terminal listed below and ground.

* APP sensor 1 terminal D or 2

* APP sensor 2 terminal C or 1

瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or open/high resistance. If the circuit/connections test

normal, replace the ECM.

瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit/connections test normal, replace the

ECM.

4. Observe the scan tool APP sensor 1 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal E or 3 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

5. Observe the scan tool APP sensor 2 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal B or 6 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

6. Connect a 3 A fused jumper wire between the APP sensor 1 signal circuit terminal E or 3 and the 5 V reference circuit terminal C or 1. Verify

the APP sensor 1 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

7. Connect a 3 A fused jumper wire between the APP sensor 2 signal circuit terminal B or 6 and the 5 V reference circuit terminal C or 1.

Verify the APP sensor 2 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

8. If all circuits/connections test normal, test or replace the Accelerator Pedal Assembly.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2482

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2482

P2122

The ECM detects that the APP sensor 1 voltage is less than 0.46 V for greater than 0.2 s.

P2123

The ECM detects that the APP sensor 1 voltage is greater than 4.75 V for greater than 0.2 s.

P2125

The APP sensor 2 voltage is less than 0.32 V or greater than 2.6 V for greater than 0.2 s.

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

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DTC P2125

- Accelerator Pedal Position (APP) Sensor 2 Circuit

DTC P2127

- Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

- Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

- Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Diagnostic Fault Information

Typical Scan Tool Data

Circuit/System Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted to the accelerator pedal

assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to pedal position. The engine control module

(ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.

Conditions for Running the DTC

P2120, P2122, P2123, P2125, P2127, P2128

* DTC P0641 or P0651 is not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2120, P2122, P2123, P2125, P2127, P2128 run continuously when the above conditions are met.

P2138

* DTC P0641, P0651, P2120, P2125 are not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2138 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2120

The APP sensor 1 voltage is less than 0.46 V or greater than 4.7 V for greater than 0.2 s.

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瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit/connections test normal, replace

the ECM.

3. Ignition ON, test for 4.8-5.2 V between the appropriate 5 V reference circuit terminal listed below and ground.

* APP sensor 1 terminal D or 2

* APP sensor 2 terminal C or 1

瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or open/high resistance. If the circuit/connections test

normal, replace the ECM.

瀚慖f greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit/connections test normal, replace the

ECM.

4. Observe the scan tool APP sensor 1 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal E or 3 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

5. Observe the scan tool APP sensor 2 voltage parameter. Verify the voltage is less than 0.3 V.

瀚慖f greater than the specified range, test the signal circuit terminal B or 6 for a short to voltage. If the circuit/connections test normal,

replace the ECM.

6. Connect a 3 A fused jumper wire between the APP sensor 1 signal circuit terminal E or 3 and the 5 V reference circuit terminal C or 1. Verify

the APP sensor 1 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

7. Connect a 3 A fused jumper wire between the APP sensor 2 signal circuit terminal B or 6 and the 5 V reference circuit terminal C or 1.

Verify the APP sensor 2 voltage parameter is greater than 4.8 V.

瀚慖f less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit/connections test

normal, replace the ECM.

8. If all circuits/connections test normal, test or replace the Accelerator Pedal Assembly.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.

* Accelerator Pedal Position Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Accelerator Pedal Position

Sensor/Service and Repair)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement,

programming, and setup

P2122

DTC P2120, P2122, P2123, P2125, P2127, P2128, or P2138

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provide an overview of each diagnostic category.

DTC Descriptors

DTC P2120

- Accelerator Pedal Position (APP) Sensor 1 Circuit

DTC P2122

- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

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* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0641 or P0651 are not set.

瀚慖f a DTC is set, refer to DTC P0641 or P0651 (ECM) (See: P Code Charts/P0641) for further diagnosis.

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.32-4.75 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

5. Observe the scan tool APP sensor 1 and 2 parameter. The scan tool should display Agree.

6. Clear the DTCs with the scan tool. Operate the vehicle within the Conditions for Running the DTC or within the conditions that you observed

from the Freeze Frame/Failure Records.

7. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P2120 or P2125 are not the only APP sensor DTCs set.

瀚慖f DTC P2120 or P2125 are the only DTCs set, replace the ECM.

8. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the accelerator pedal.

2. Ignition OFF for 1 minute, test for less than 5 ohm between the appropriate low reference circuit terminal listed below and ground.

* APP sensor 1 terminal F or 4

* APP sensor 2 terminal A or 5

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Circuit/System Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted to the accelerator pedal

assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to pedal position. The engine control module

(ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.

Conditions for Running the DTC

P2120, P2122, P2123, P2125, P2127, P2128

* DTC P0641 or P0651 is not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2120, P2122, P2123, P2125, P2127, P2128 run continuously when the above conditions are met.

P2138

* DTC P0641, P0651, P2120, P2125 are not set.

* The ignition is ON or the engine is running.

* The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.

* DTC P2138 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2120

The APP sensor 1 voltage is less than 0.46 V or greater than 4.7 V for greater than 0.2 s.

P2122

The ECM detects that the APP sensor 1 voltage is less than 0.46 V for greater than 0.2 s.

P2123

The ECM detects that the APP sensor 1 voltage is greater than 4.75 V for greater than 0.2 s.

P2125

The APP sensor 2 voltage is less than 0.32 V or greater than 2.6 V for greater than 0.2 s.

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

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Enabled while the Throttle Sweep Test is in progress.

6. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in

order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List -

Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) and perform the appropriate diagnostic

procedure.

P2120

DTC P2120, P2122, P2123, P2125, P2127, P2128, or P2138

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provide an overview of each diagnostic category.

DTC Descriptors

DTC P2120

- Accelerator Pedal Position (APP) Sensor 1 Circuit

DTC P2122

- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

DTC P2125

- Accelerator Pedal Position (APP) Sensor 2 Circuit

DTC P2127

- Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

- Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

- Accelerator Pedal Position (APP) Sensor 1-2 Correlation

Diagnostic Fault Information

Typical Scan Tool Data

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2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2476

6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Warning

Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

1. Ignition OFF, verify the following conditions do not exist with the throttle body assembly:

* A throttle blade that is not in the rest position

* A throttle blade that is binding open or closed

* A throttle blade that is free to move open or closed without spring pressure

瀚慖f a condition is found, replace the throttle body assembly.

Note: Disconnecting the throttle body harness connector may cause additional DTCs to set.

2. Ignition OFF, disconnect the harness connector at the throttle body assembly.

3. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and ground.

* TAC Motor Control Closed circuit terminal A

* TAC Motor Control Open circuit terminal B

瀚慖f test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and B+.

* TAC Motor Control Closed circuit terminal A

* TAC Motor Control Open circuit terminal B

瀚慖f the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.

5. Ignition OFF, set the DMM to the 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.

Note:

* The DMM Min/Max Recording Mode and the response time of 1 ms must be reset after testing each circuit or a lower voltage will be

recorded.

* The ignition must be OFF and the ECM completely powered down before testing each circuit or a lower voltage will be recorded.

6. Ignition OFF, measure the voltage using the DMM Min/Max Recording Mode function on each circuit listed below as the ignition is turned

ON. The Max voltage should be within 1 V of B+.

* TAC Motor Control Closed circuit terminal A

* TAC Motor Control Open circuit terminal B

瀚慖f not within the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

7. If all circuits and connections test normal, replace the throttle body assembly.

Repair Instructions

* Throttle Body Assembly Replacement (See: Powertrain Management/Fuel Delivery and Air Induction/Throttle Body/Service and

Repair/Removal and Replacement)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement,

programming, and setup

Repair Verification

1. Install any components that have been removed or replaced during diagnosis.

2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.

3. Clear the DTCs with a scan tool.

4. Turn OFF the ignition for 60 s.

Note: If the Throttle Sweep Test is not available on the scan tool, use the accelerator to perform the test. Refer to Diagnostic Aids for further

details.

5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display

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- Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times.

- Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the

procedure several times.

The TAC Motor parameter should display Enabled. If Disabled is displayed, continue diagnosis in Circuit/System Testing.

* Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing

the throttle valve not to close.

* A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.

* A low battery condition may cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Note: A low battery voltage or charging system condition may cause a DTC to set.

1. Ignition ON, observe the DTC information with a scan tool. DTC P0120, P0122, P0123, P0220, P0222, P0223, P0562, P0621, P0622, or

P2135 should not set.

瀚慖f a DTC sets, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble

Code (DTC) List - Vehicle) for further diagnosis.

2. Clear the DTCs with a scan tool. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power

down.

3. Ignition ON, observe the scan tool TAC Motor parameter. The reading should display Enabled.

4. Observe the DTC information with a scan tool. DTC P1516, P2101, P2119, or P2176 should not set.

Note:

* If the Throttle Sweep Test is not available on the scan tool, use the accelerator to perform the test. Refer to Diagnostic Aids for further

details.

* If there is a condition with the throttle body, the TAC Motor Command parameter will go to 99 % for a predetermined amount of time

and then a DTC sets. Once a DTC is set, the TAC Motor Command parameter will go to 0 % and the TAC Motor parameter will display

Disabled.

5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display

Enabled while the Throttle Sweep Test is in progress.

Note: Before replacing the throttle body assembly, make sure the throttle control circuits are not shorted to B+.

瀚慖f not the specified value, replace the throttle body assembly.

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Conditions for Running the DTC

P1516 and P2101

* DTC P0606 and P1682 is not set.

* The run/crank or powertrain relay voltage is greater than 6 V and reduced power is not active.

* The engine is running or the following conditions are met:

- The engine is not running.

- The ignition voltage is greater than 11 V.

- The TAC system is not in the Battery Saver mode.

- The ECM is commanding the throttle.

- The ECM has learned the minimum throttle position.

* DTC P1516 and P2101 run continuously when the above conditions are met.

P2119

* The ignition is ON.

* The run/crank or powertrain relay voltage is greater than 6 V and reduced power is not active.

* The TP sensor 1 voltage is greater than 1.7 V

* The ECM is not commanding the throttle blade.

* DTC P2119 runs continuously when the above conditions are met.

P2176

* DTCs P0120, P0121, P0122, P0123, P0220, P0222, P0223, or P1682 is not set.

* The ignition is ON.

* The run/crank or powertrain relay voltage is greater than 6 V and reduced power is not active.

* The ECM enable the minimum throttle learn procedure.

* DTC P2176 run continuously when the above conditions are met.

Conditions for Setting the DTC

P1516

The actual throttle position does not match the predicted throttle position for greater than 1 s.

P2101

The actual throttle position does not match the predicted throttle position for greater than 1 s.

P2119

The ECM detects that the throttle blade did not return to the default position when the TAC motor is de-energized for greater than 1 s.

P2176

The ECM detects that both throttle position (TP) sensors were greater than a predetermined voltage during the minimum throttle learn procedure for

greater than 2 s.

Action Taken When the DTC Sets

P1516, P2101, and P2176

* DTCs P1516, P2101, and P2176 are Type A DTCs.

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions, the control module commands the engine OFF.

P2119

* DTC P2119 is a Type C DTC.

* The driver information center, if equipped, may display a message.

Conditions for Clearing the MIL/DTC

* DTCs P1516, P2101, and P2176 are Type A DTCs.

* DTC P2119 is a Type C DTC.

Diagnostic Aids

* If the Throttle Sweep Test is not available on the scan tool, observe the scan tool TAC Motor parameter while performing the following tests:

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2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2473

瀚慖f not within the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

7. If all circuits and connections test normal, replace the throttle body assembly.

Repair Instructions

* Throttle Body Assembly Replacement (See: Powertrain Management/Fuel Delivery and Air Induction/Throttle Body/Service and

Repair/Removal and Replacement)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for Engine Control Module replacement,

programming, and setup

Repair Verification

1. Install any components that have been removed or replaced during diagnosis.

2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.

3. Clear the DTCs with a scan tool.

4. Turn OFF the ignition for 60 s.

Note: If the Throttle Sweep Test is not available on the scan tool, use the accelerator to perform the test. Refer to Diagnostic Aids for further

details.

5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display

Enabled while the Throttle Sweep Test is in progress.

6. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in

order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List -

Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) and perform the appropriate diagnostic

procedure.

P2119

DTC P1516, P2101, P2119, or P2176

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptors

DTC P1516

- Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance

DTC P2101

- Throttle Actuator Position Performance

DTC P2119

- Throttle Closed Position Performance

DTC P2176

- Minimum Throttle Position Not Learned

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the control circuits of the throttle actuator control

(TAC) motor. The ECM monitors the duty cycle that is required to actuate the throttle valve. The ECM monitors the throttle position (TP) sensors 1

and 2 to determine the actual throttle valve position.

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瀚慖f a DTC sets, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic Trouble

Code (DTC) List - Vehicle) for further diagnosis.

2. Clear the DTCs with a scan tool. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power

down.

3. Ignition ON, observe the scan tool TAC Motor parameter. The reading should display Enabled.

4. Observe the DTC information with a scan tool. DTC P1516, P2101, P2119, or P2176 should not set.

Note:

* If the Throttle Sweep Test is not available on the scan tool, use the accelerator to perform the test. Refer to Diagnostic Aids for further

details.

* If there is a condition with the throttle body, the TAC Motor Command parameter will go to 99 % for a predetermined amount of time

and then a DTC sets. Once a DTC is set, the TAC Motor Command parameter will go to 0 % and the TAC Motor parameter will display

Disabled.

5. Perform the Throttle Sweep Test while observing the TAC Motor parameter with a scan tool. The TAC Motor parameter should display

Enabled while the Throttle Sweep Test is in progress.

Note: Before replacing the throttle body assembly, make sure the throttle control circuits are not shorted to B+.

瀚慖f not the specified value, replace the throttle body assembly.

6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Warning

Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

1. Ignition OFF, verify the following conditions do not exist with the throttle body assembly:

* A throttle blade that is not in the rest position

* A throttle blade that is binding open or closed

* A throttle blade that is free to move open or closed without spring pressure

瀚慖f a condition is found, replace the throttle body assembly.

Note: Disconnecting the throttle body harness connector may cause additional DTCs to set.

2. Ignition OFF, disconnect the harness connector at the throttle body assembly.

3. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and ground.

* TAC Motor Control Closed circuit terminal A

* TAC Motor Control Open circuit terminal B

瀚慖f test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Ignition ON, verify that a test lamp does not illuminate between each control circuit listed below and B+.

* TAC Motor Control Closed circuit terminal A

* TAC Motor Control Open circuit terminal B

瀚慖f the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.

5. Ignition OFF, set the DMM to the 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.

Note:

* The DMM Min/Max Recording Mode and the response time of 1 ms must be reset after testing each circuit or a lower voltage will be

recorded.

* The ignition must be OFF and the ECM completely powered down before testing each circuit or a lower voltage will be recorded.

6. Ignition OFF, measure the voltage using the DMM Min/Max Recording Mode function on each circuit listed below as the ignition is turned

ON. The Max voltage should be within 1 V of B+.

* TAC Motor Control Closed circuit terminal A

* TAC Motor Control Open circuit terminal B

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2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2471

greater than 2 s.

Action Taken When the DTC Sets

P1516, P2101, and P2176

* DTCs P1516, P2101, and P2176 are Type A DTCs.

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions, the control module commands the engine OFF.

P2119

* DTC P2119 is a Type C DTC.

* The driver information center, if equipped, may display a message.

Conditions for Clearing the MIL/DTC

* DTCs P1516, P2101, and P2176 are Type A DTCs.

* DTC P2119 is a Type C DTC.

Diagnostic Aids

* If the Throttle Sweep Test is not available on the scan tool, observe the scan tool TAC Motor parameter while performing the following tests:

- Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times.

- Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the

procedure several times.

The TAC Motor parameter should display Enabled. If Disabled is displayed, continue diagnosis in Circuit/System Testing.

* Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing

the throttle valve not to close.

* A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.

* A low battery condition may cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Note: A low battery voltage or charging system condition may cause a DTC to set.

1. Ignition ON, observe the DTC information with a scan tool. DTC P0120, P0122, P0123, P0220, P0222, P0223, P0562, P0621, P0622, or

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- Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance

DTC P2101

- Throttle Actuator Position Performance

DTC P2119

- Throttle Closed Position Performance

DTC P2176

- Minimum Throttle Position Not Learned

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) controls the throttle valve by applying a varying voltage to the control circuits of the throttle actuator control

(TAC) motor. The ECM monitors the duty cycle that is required to actuate the throttle valve. The ECM monitors the throttle position (TP) sensors 1

and 2 to determine the actual throttle valve position.

Conditions for Running the DTC

P1516 and P2101

* DTC P0606 and P1682 is not set.

* The run/crank or powertrain relay voltage is greater than 6 V and reduced power is not active.

* The engine is running or the following conditions are met:

- The engine is not running.

- The ignition voltage is greater than 11 V.

- The TAC system is not in the Battery Saver mode.

- The ECM is commanding the throttle.

- The ECM has learned the minimum throttle position.

* DTC P1516 and P2101 run continuously when the above conditions are met.

P2119

* The ignition is ON.

* The run/crank or powertrain relay voltage is greater than 6 V and reduced power is not active.

* The TP sensor 1 voltage is greater than 1.7 V

* The ECM is not commanding the throttle blade.

* DTC P2119 runs continuously when the above conditions are met.

P2176

* DTCs P0120, P0121, P0122, P0123, P0220, P0222, P0223, or P1682 is not set.

* The ignition is ON.

* The run/crank or powertrain relay voltage is greater than 6 V and reduced power is not active.

* The ECM enable the minimum throttle learn procedure.

* DTC P2176 run continuously when the above conditions are met.

Conditions for Setting the DTC

P1516

The actual throttle position does not match the predicted throttle position for greater than 1 s.

P2101

The actual throttle position does not match the predicted throttle position for greater than 1 s.

P2119

The ECM detects that the throttle blade did not return to the default position when the TAC motor is de-energized for greater than 1 s.

P2176

The ECM detects that both throttle position (TP) sensors were greater than a predetermined voltage during the minimum throttle learn procedure for

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2469

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2469

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, verify the scan tool Fuel Tank Level Remaining parameter is between 4-98 percent.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the secondary fuel level sensor.

2. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal B and ground.

瀚慖f greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests

normal, replace the ECM.

3. Ignition ON, install a 3 A fused jumper wire between the secondary signal circuit terminal C and the low reference circuit terminal B. Verify

the scan tool Fuel Tank Level Remaining parameter display is greater than 98 percent.

瀚慖f less than the specified range, test the secondary signal circuit for a short to voltage or an open/high resistance. If the circuit tests

normal, replace the ECM.

4. If all circuits test normal, test or replace the secondary fuel level sensor.

Component Testing

1. Ignition OFF, remove the secondary fuel level sender.

2. While sweeping the fuel level sensor through its full range of motion, test for a minimum resistance value of less than 41 ohm and a

maximum value greater than 119 ohm between the secondary signal terminal B and the low reference terminal C.

瀚慖f not within the specified range, replace the secondary fuel level sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Fuel Level Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair) for

the 6.0L (LFA) engine

* Fuel Level Sensor Replacement (2500 - 98.4L (26 gal) Tank - Front) (See: Powertrain Management/Computers and Control Systems/Fuel

Level Sensor/Service and Repair/Fuel Level Sensor Replacement (2500 - 98.4L (26 Gal) Tank - Front))Fuel Level Sensor Replacement

(2500 - 43.5L (11.5 gal) Tank - Rear) (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and

Repair/Fuel Level Sensor Replacement (2500 - 43.5L (11.5 Gal) Tank - Rear))Fuel Level Sensor Replacement (1500 Series) (See:

Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair/Fuel Level Sensor Replacement (1500

Series))Fuel Level Sensor Replacement (1500 Series w/E85) (See: Powertrain Management/Computers and Control Systems/Fuel Level

Sensor/Service and Repair/Fuel Level Sensor Replacement (1500 Series w/E85)) for the 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L engine

* Control Module References (See: Testing and Inspection/Programming and Relearning) for the ECM replacement, programming and setup

P2101

DTC P1516, P2101, P2119, or P2176

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

Sunday, November 29, 2020

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2468

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2468

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC P2068

- Fuel Level Sensor 2 High Voltage

Diagnostic Fault Information

Circuit/System Description

The primary fuel level sensor and the secondary fuel level sensor change resistance in response to the fuel level. The engine control module (ECM)

monitors the signal circuit of the primary fuel level sensor, the secondary fuel level sensor, and the type of fuel in order to determine the fuel level.

For regular unleaded fuel the ECM monitors a constant signal. When the vehicle has approximately 20% or greater ethanol for E85 fuel

applications, the ECM controls a pulse cycle signal where it monitors the signal and calculates the fuel level percentage only during the on pulse of

approximately 100 ms.

When the fuel tanks are full, the sensor resistances of both fuel level sensors are low and the ECM senses a low signal voltage on both the signal

circuits of the primary fuel level sensor and the secondary fuel level sensor. When the fuel tanks are empty, the resistances of the fuel level sensors

are high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the primary fuel level sensor and the secondary fuel level

sensor in order to calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the

instrument cluster in order to control the fuel gauge.

Conditions for Running the DTC

* The ignition is ON, with the engine running.

* The system voltage is between 9-16 V.

Conditions for Setting the DTC

* The secondary sensor output is greater than 3.5 V.

* The above condition is present for greater than 30 seconds.

Action Taken When the DTC Sets

* The fuel gauge defaults to empty.

* The low fuel indicator illuminates.

* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure

Records on the scan tool.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.

* The history DTC clears after 40 malfunction-free warm-up cycles.

Reference Information

Schematic Reference

Instrument Cluster Schematics (See: Diagrams/Electrical Diagrams/Instrument Panel, Gauges and Warning Indicators/System Diagram/Instrument

Cluster Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Instrument Cluster Description and Operation (See: Instrument Panel, Gauges and Warning Indicators/Description and Operation/Instrument

Cluster)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2467

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2467

Cluster Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Instrument Cluster Description and Operation (See: Instrument Panel, Gauges and Warning Indicators/Description and Operation/Instrument

Cluster)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, verify the scan tool Fuel Tank Level Remaining parameter is between 4-98 percent.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the secondary fuel level sensor.

2. Ignition ON, verify that the scan tool Fuel Tank Level Remaining parameter display is less than 4 percent.

瀚慖f greater than the specified value, test the secondary signal circuit terminal C for a short to ground. If the circuit tests normal, replace the

ECM.

3. If all circuits test normal, test or replace the secondary fuel level sensor.

Component Testing

1. Ignition OFF, remove the secondary fuel level sender.

2. While sweeping the fuel level sensor through its full range of motion, test for a minimum resistance value of less than 41 ohm and a

maximum value greater than 119 ohm between the signal terminal C and the low reference terminal B.

瀚慖f not within the specified range, replace the secondary fuel level sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Fuel Level Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair) for

the 6.0L (LFA) engine

* Fuel Level Sensor Replacement (2500 - 98.4L (26 gal) Tank - Front) (See: Powertrain Management/Computers and Control Systems/Fuel

Level Sensor/Service and Repair/Fuel Level Sensor Replacement (2500 - 98.4L (26 Gal) Tank - Front))Fuel Level Sensor Replacement

(2500 - 43.5L (11.5 gal) Tank - Rear) (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and

Repair/Fuel Level Sensor Replacement (2500 - 43.5L (11.5 Gal) Tank - Rear))Fuel Level Sensor Replacement (1500 Series) (See:

Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair/Fuel Level Sensor Replacement (1500

Series))Fuel Level Sensor Replacement (1500 Series w/E85) (See: Powertrain Management/Computers and Control Systems/Fuel Level

Sensor/Service and Repair/Fuel Level Sensor Replacement (1500 Series w/E85)) for the 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L engine

* Control Module References (See: Testing and Inspection/Programming and Relearning) for the ECM replacement, programming and setup

P2068

DTC P2068

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2466

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2466

Sensor/Service and Repair/Fuel Level Sensor Replacement (1500 Series w/E85)) for the 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L engine

* Control Module References (See: Testing and Inspection/Programming and Relearning) for the ECM replacement, programming and setup

P2067

DTC P2067

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC P2067

- Fuel Level Sensor 2 Low Voltage

Diagnostic Fault Information

Circuit/System Description

The primary fuel level sensor and the secondary fuel level sensor change resistance in response to the fuel level. The engine control module (ECM)

monitors the signal circuit of the primary fuel level sensor, the secondary fuel level sensor, and the type of fuel in order to determine the fuel level.

For regular unleaded fuel the ECM monitors a constant signal. When the vehicle has approximately 20% or greater ethanol for E85 fuel

applications, the ECM controls a pulse cycle signal where it monitors the signal and calculates the fuel level percentage only during the on pulse of

approximately 100 ms.

When the fuel tanks are full, the sensor resistances of both fuel level sensors are low and the ECM senses a low signal voltage on both the signal

circuits of the primary fuel level sensor and the secondary fuel level sensor. When the fuel tanks are empty, the resistances of the fuel level sensors

are high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the primary fuel level sensor and the secondary fuel level

sensor in order to calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the

instrument cluster in order to control the fuel gauge.

Conditions for Running the DTC

* The ignition is ON, with the engine running.

* The system voltage is between 11-18 V.

Conditions for Setting the DTC

* The secondary sender output is less than 0.5 V.

* The above condition is present for greater than 30 seconds.

Action Taken When the DTC Sets

* The fuel gauge defaults to empty.

* The low fuel indicator illuminates.

* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure

Records on the scan tool.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.

* The history DTC clears after 40 malfunction-free warm-up cycles.

Reference Information

Schematic Reference

Instrument Cluster Schematics (See: Diagrams/Electrical Diagrams/Instrument Panel, Gauges and Warning Indicators/System Diagram/Instrument

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2465

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2465

Conditions for Setting the DTC

* The ECM detects a change in fuel level less than 3 liters (0.8 gallon) over a distance greater than 282 km (175 miles).

* The vehicle is at rest and the primary fuel tank increases by 3 liters (0.8 gallon) and the secondary fuel tank does not decrease by 3 liters (0.8

gallon) when the transfer pump is on greater than 500 seconds.

Action Taken When the DTC Sets

* The fuel gauge defaults to empty.

* The low fuel indicator illuminates.

* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure

Records on the scan tool.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.

* The history DTC clears after 40 malfunction-free warm-up cycles.

Reference Information

Schematic Reference

Instrument Cluster Schematics (See: Diagrams/Electrical Diagrams/Instrument Panel, Gauges and Warning Indicators/System Diagram/Instrument

Cluster Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Instrument Cluster Description and Operation (See: Instrument Panel, Gauges and Warning Indicators/Description and Operation/Instrument

Cluster)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Component Testing

1. Ignition OFF, remove the secondary fuel level sender and verify there are no obstructions interfering with the fuel level sender.

瀚慖f any interference is present, repair the fuel sender interference.

2. Ignition OFF, disconnect the harness connector at the secondary fuel level sensor.

3. While sweeping the fuel level sensor through its full range of motion, test for a minimum resistance value of less than 41 ohm and a

maximum value greater than 119 ohm between the signal terminal C and the low reference terminal B.

瀚慖f not within the specified range, replace the secondary fuel level sensor.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Fuel Level Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair) for

the 6.0L (LFA) engine

* Fuel Level Sensor Replacement (2500 - 98.4L (26 gal) Tank - Front) (See: Powertrain Management/Computers and Control Systems/Fuel

Level Sensor/Service and Repair/Fuel Level Sensor Replacement (2500 - 98.4L (26 Gal) Tank - Front))Fuel Level Sensor Replacement

(2500 - 43.5L (11.5 gal) Tank - Rear) (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and

Repair/Fuel Level Sensor Replacement (2500 - 43.5L (11.5 Gal) Tank - Rear))Fuel Level Sensor Replacement (1500 Series) (See:

Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair/Fuel Level Sensor Replacement (1500

Series))Fuel Level Sensor Replacement (1500 Series w/E85) (See: Powertrain Management/Computers and Control Systems/Fuel Level

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2464

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2464

6. If all circuits test normal, test or replace the IMS.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

Note:

* Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (See: Transmission and Drivetrain/Automatic

Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/6L45/6L50/6L80/6L90 - Automatic

Transmission/Control Solenoid Valve and Transmission Control Module Assembly Inspection) before replacing any internal transmission

components.

* Perform the Service Fast Learn Adapts (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and

Inspection/Programming and Relearning) following all transmission repairs.

* Manual Shift Shaft Position Switch Replacement (See: Powertrain Management/Computers and Control Systems/Sensors and Switches -

Computers and Control Systems/Transmission Position Sensor/Switch/Service and Repair/6L45/6L50/6L80/6L90 - Automatic Transmission

)for internal mode switch (IMS) replacement.

* Control Module References (See: Testing and Inspection/Programming and Relearning)for control solenoid valve assembly replacement,

setup, and programming.

P2066

DTC P2066

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC P2066

- Fuel Level Sensor 2 Performance

Diagnostic Fault Information

Circuit/System Description

The primary fuel level sensor and the secondary fuel level sensor change resistance in response to the fuel level. The engine control module (ECM)

monitors the signal circuit of the primary fuel level sensor, the secondary fuel level sensor, and the type of fuel in order to determine the fuel level.

For regular unleaded fuel the ECM monitors a constant signal. When the vehicle has approximately 20% or greater ethanol for E85 fuel

applications, the ECM controls a pulse cycle signal where it monitors the signal and calculates the fuel level percentage only during the on pulse of

approximately 100 ms.

When the fuel tanks are full, the sensor resistances of both fuel level sensors are low and the ECM senses a low signal voltage on both the signal

circuits of the primary fuel level sensor and the secondary fuel level sensor. When the fuel tanks are empty, the resistances of the fuel level sensors

are high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the primary fuel level sensor and the secondary fuel level

sensor in order to calculate the percentage of remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the

instrument cluster in order to control the fuel gauge.

This diagnostic tests for a stuck fuel level sensor signal. The ECM sets this DTC if the fuel level sensor signal appears to be stuck based on a lack

of signal variation expected during normal operation.

Conditions for Running the DTC

* The engine is running.

* Fuel level is greater than 32 liters (8.5 gallons).

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2463

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2463

* Inline Harness Connector End Views (See: Power and Ground Distribution/Multiple Junction Connector/Diagrams)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Description and Operation

* Electronic Component Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and

Operation/6L45/6L50/6L80/6L90 - Automatic Transmission/Electronic Component Description)

* Transmission General Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and

Operation/6L45/6L50/6L80/6L90 - Automatic Transmission/Transmission General Description)

* Transmission Component and System Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and

Operation/6L45/6L50/6L80/6L90 - Automatic Transmission/Transmission Component and System Description)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning)for scan tool information

Circuit/System Verification

1. Perform the Range Selector Lever Cable Adjustment (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Shift

Linkage/Shift Cable/Adjustments) procedure to verify proper adjustment.

2. Ignition ON, observe the scan tool IMS parameter while moving the gear shift lever from Park, through all gear selector positions, and back

to Park. The parameter should match each gear range that is selected. Refer to Transmission Internal Mode Switch Logic (See:

Specifications/Mechanical Specifications/Automatic Transmission/Transaxle/System Specifications/6L45/6L50/6L80/6L90 - Automatic

Transmission/Transmission Internal Mode Switch Logic).

3. Observe the scan tool Engine Control Module P/N switch parameter with the gear selector in Park and Neutral position. The parameter

should display Park in park position and Neutral in neutral position.

4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Note: You must perform Circuit/System Verification first.

1. Ignition OFF, remove the automatic transmission fluid pan. Refer to Automatic Transmission Fluid, Fluid Pan and/or Filter Replacement ().

2. Disconnect the IMS connector at the Q8 control solenoid valve assembly.

Note: Under certain driving conditions, DTC P182E could set due to an intermittent low voltage fault on the P/N signal circuit, before

conditions for setting DTC P0851 are met.

3. Ignition ON, verify the scan tool engine control module (ECM) P/N switch displays In Gear.

瀚慖f not the specified value, test the P/N signal circuit for a short to ground. If the circuit tests normal, replace the engine control module.

4. Verify the scan tool IMS A/B/C/P parameter displays HI for all four signal circuits.

瀚慖f not the specified value, replace the Q8 control solenoid valve assembly.

5. Connect a 3A fused jumper wire between each transmission range signal circuit terminals listed below and the IMS ground circuit. The

appropriate scan tool IMS A/B/C/P parameter should display LOW when the terminal is connected to the IMS ground circuit.

* Switch Signal A: terminal E to terminal A

* Switch Signal B: terminal D to terminal A

* Switch Signal C: terminal C to terminal A

* Switch Signal P: terminal P to terminal A

瀚慖f not the specified value, replace the Q8 control solenoid valve assembly.