2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2948

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2948

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 Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

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

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

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

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

U2135

DTC U2105-U2199

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 U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2891

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2891

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 Testing

1. Ignition OFF, disconnect the harness connector of the yaw rate sensor.

2. Ignition ON, verify that a test lamp illuminates between the module voltage circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

EBCM.

3. Ignition OFF, test for less than 5 ohms between the module ground circuits and ground.

瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

4. If all circuits test normal, replace the yaw rate sensor.

Repair Instructions

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

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

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

* ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and

Operation/ABS Description and Operation) for the ABS - Hybrid

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Less than 3900 kg

(8600 lb) GVW

* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement (See: Brakes and Traction Control/Antilock Brakes / Traction

Control Systems/Yaw Rate Sensor/Service and Repair/Less than 3900 kg (8600 lb) GVW) for the ABS - Non-Hybrid Greater than/Equal to

3900 kg (8600 lb) GVW

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

U2107

DTC U2105-U2199

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 U2142 00

- Lost Communication With Yaw Rate Sensor (YRS)

Circuit/System Description

Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating

information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be

exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an

availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the

ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2100

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2100

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)

Circuit/System Verification

1. Engine operating, observe the DTC information with a scan tool. DTC P0480, P0481, or P0482 should not be set.

2. Command the cooling fans ON and OFF at high speed while observing the scan tool circuit test status parameters listed below:

* FC Relay 1 Ckt Open, Short Gnd, and Short Volts Test Status

* FC Relay 2 Ckt Open, Short Gnd, and Short Volts Test Status

* FC Relay 3 Ckt Open, Short Gnd, and Short Volts Test Status

The parameters should display OK or Not Run in each of the commanded states.

3. 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, open the hood to disable the Auto-Stop function.

2. Ignition ON, verify the scan tool hood position parameter displays Open.

瀚慖f the hood position does not display Open, refer to DTC P254F (See: P Code Charts/P254F).

3. Ignition OFF, disconnect all 5 cooling fan relays.

4. Ignition ON, verify that a test lamp illuminates between ground and the ignition circuit terminal of each relay listed below:

* FAN LO Relay terminal 85

* FAN MID 1 Relay terminal 85

* FAN CNTRL Relay terminal 86

* FAN MID 2 Relay terminal 86

* FAN HI Relay terminal 86

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and

the ignition circuit fuse is open, test all the components connected to the ignition voltage circuit and replace as necessary.

5. Set the DMM on the diode setting. Connect the black lead to ground. Connect the red lead of the DMM to a control circuit terminal listed

below:

* FAN LO Relay terminal 86

* FAN MID 1 Relay terminal 86

* FAN CNTRL Relay terminal 85

* FAN MID 2 Relay terminal 85

* FAN HI Relay terminal 85

The DMM should display OL.

瀚慖f less than the specified range, test the appropriate relay coil control circuit for a short to ground. If the circuit tests normal, replace the

K20 ECM.

6. Command the appropriate cooling fan relay ON and OFF with a scan tool. The DMM should transition from OL when commanded OFF to

less than 1 V when commanded ON.

瀚慖f the circuit voltage does not correspond to the specified values, test the control circuit for an open/high resistance or for a short to

voltage. If the circuit tests normal, replace the K20 ECM.

7. If all circuits test normal, test or replace the appropriate KR20 relay.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2049

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2049

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

1. With the engine running, monitor the following ignition control (IC) circuit status parameters with a scan tool:

* Cylinder 1-8 IC Ckt. Short Gnd Test Status

* Cylinder 1-8 IC Ckt. Open Test Status

* Cylinder 1-8 IC Ckt. Short to Volts Test Status

瀚慐ach parameter should display OK.

2. With the engine running, observe the Misfire Current counters with a scan tool.

瀚慣he counters should not be incrementing.

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed

from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. With the engine running, monitor the Cylinder 1-8 IC Circuit Status parameters with a scan tool.

瀚慖f a short to GND or Open status test displays FAULT, test for an open/high resistance or short to ground on the affected IC circuit

terminal C.

瀚慖f a short to volts status test displays FAULT, test for a short to voltage on the affected IC circuit terminal C.

Important: A high resistance on any IC circuit can cause a misfire condition before DTCs P0351-P0358 set.

2. Exchange the affected ignition coil/module with the ignition coil/module of a cylinder that is not affected.

3. Start and run the engine. With a scan tool, monitor the IC circuit parameters and the Misfire Current counters.

瀚慖f the circuit status fault identified or the misfire transfers with the ignition coil/module, replace the ignition coil/module assembly.

瀚慖f the circuit status fault identified or the misfire does not transfer with the ignition coil/module, replace the ECM.

Repair Instructions

* Ignition Coil Replacement (See: Powertrain Management/Ignition System/Ignition Coil/Service and Repair)

* Engine Control Module Replacement (See: Powertrain Management/Computers and Control Systems/Engine Control Module/Service and

Repair)

* Engine Control Module Programming and Setup (See: Powertrain Management/Computers and Control Systems/Engine Control

Module/Testing and Inspection)

Repair Verification

Important: An IC circuit fault condition will result in an engine misfire, and under certain driving conditions could possibly overheat the

3-way catalytic converter.

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

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

3. Start and run the engine. With a scan tool, monitor the IC circuit status parameters. All IC circuit status parameters should display OK.

瀚慖f another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code

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

4. To verify that the performance of the catalytic converter has not been affected by the condition that set this DTC, perform the Repair

Verification for DTC P0420 or P0430. Refer to DTC P0420 or P0430 (See: P Code Charts/P0420).

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2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2000

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

Special Tools

J 26792 HEI Spark Tester

Circuit/System Verification

1. Verify that no other DTCs are set.

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

Code (DTC) List - Vehicle).

2. Engine idling, verify there is no abnormal engine noise.

瀚慖f there is an abnormal engine noise, refer to Symptoms - Engine Mechanical (See: Engine, Cooling and Exhaust/Engine/Testing and

Inspection/Symptom Related Diagnostic Procedures/Symptoms - Engine Mechanical).

3. Observe the Misfire Current Counters with a scan tool. The Misfire Current Counters should not be incrementing. Random misfires that are

not steadily incrementing may be normal.

4. Operate the vehicle within the Conditions for Running the DTC to verify that 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

Important: You must perform the Circuit/System Verification first.

1. Verify that the following conditions do not exist:

* The fuel injector wire harness electrical connectors are connected to the wrong fuel injectors. Refer to Engine Controls Schematics (See:

Diagrams/Electrical Diagrams/Powertrain Management/System Diagram).

* Engine vacuum leaks

* Fuel pressure that is too low or too high-Refer to Fuel System Diagnosis (w/o FPCM) (See: Powertrain Management/Computers and

Control Systems/Testing and Inspection/Component Tests and General Diagnostics)Fuel System Diagnosis (FPCM) (See: Powertrain

Management/Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics).

* Contaminated fuel-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool) (See: Powertrain Management/Computers

and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis

(Without Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool) (See: Powertrain Management/Fuel Delivery and Air

Induction/Fuel/Testing and Inspection/Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool)).

* Restricted exhaust system-Refer to Restricted Exhaust (See: Engine, Cooling and Exhaust/Exhaust System/Testing and

Inspection/Restricted Exhaust).

瀚慖f you find any of the above conditions, repair as necessary.

2. Verify that there is no misfire on cylinders 1, 4, 6, or 7 due to cylinder deactivation-Refer to Cylinder Deactivation (Active Fuel

Management) System Diagnosis (See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Component Tests

and General Diagnostics/Cylinder Deactivation (Active Fuel Management) System Diagnosis).

3. Ignition OFF, install the J 26792 - Tester to the spark plug wire boot of the misfiring cylinder.

Note: An erratic or weak spark is considered a no spark condition.

4. Attempt to start the engine and observe the J 26792 - Tester. The spark tester should spark.

瀚慖f there is no spark, test the spark plug wire for the correct resistance, refer to Ignition System Specifications (See: Powertrain

Management/Ignition System/Specifications) and Spark Plug Wire Inspection (See: Engine, Cooling and Exhaust/Engine/Tune-up and

Engine Performance Checks/Ignition Cable/Testing and Inspection).

瀚慖f the spark plug wire tests normal, refer to Electronic Ignition System Diagnosis (See: Powertrain Management/Computers and Control

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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1739

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

Special Tools

DT-47825-20 Adapter Harness

Circuit/System Verification

1. Operate the vehicle in second gear long enough to ensure at least a 3掳C (5掳F) rise in TCM temperature, then operate the vehicle in Park for 5

seconds.

2. Place the gear selector in Reverse for 5 seconds and then idle the vehicle in Park for 5 seconds. Verify with a scan tool the following test

status parameters display OK:

* Shift Sol. 1 Ctrl. Ckt. High Voltage Test Status

* Shift Sol. 1 Ctrl. Ckt. Open Test Status

* Shift Sol. 1 Ctrl. Ckt. Low Voltage Test Status

3. 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 the Circuit/System Verification first.

1. Ignition OFF, remove the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly

Replacement (See: Powertrain Management/Transmission Control Systems/Actuators and Solenoids - Transmission and

Drivetrain/Actuators and Solenoids - A/T/Shift Solenoid/Service and Repair).

2. 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/6T70/6T75 - Automatic Transmission/Control

Solenoid Valve and Transmission Control Module Assembly Inspection).

3. Place the control solenoid valve assembly on a clean work surface near the transmission assembly.

4. Connect DT-47825-20 - jumper harness between the vehicle wire harness electrical connector, and the control solenoid valve assembly

electrical connector.

5. Ignition ON, verify with a scan tool the following test status parameters display OK:

* Shift Sol. 1 Ctrl. Ckt. High Voltage Test Status

* Shift Sol. 1 Ctrl. Ckt. Open Test Status

* Shift Sol. 1 Ctrl. Ckt. Low Voltage Test Status

瀚慖f any test status parameter displays Fault or Malfunction, replace the control solenoid valve assembly.

Repair Instructions

Important:

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

Inspection/Programming and Relearning) following all transmission related repairs.

* Before replacing the TCM, 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/6T70/6T75 - Automatic Transmission/Control Solenoid Valve and Transmission Control Module Assembly Inspection).

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

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

and programming

AF40-6 - Automatic Transmission

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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1849

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. Observe the DTC information with a scan tool. DTC P2178 or P2188 should not be set.

瀚慖f there are other DTCs set besides DTC P2178 or P2188, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic

Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) to diagnosis the applicable DTC.

2. Ignition ON, observe the BARO pressure parameter and compare the reading on the scan tool to the barometric pressure table. Refer to

Altitude Versus Barometric Pressure (See: Powertrain Management/Computers and Control Systems/Specifications/Altitude Versus

Barometric Pressure).

瀚慖f the BARO pressure is not within the range specified for your altitude, refer to DTC P2227, P2228, or P2229 (LAU) ( See: P Code

Charts/P2227).

3. Engine at normal operating temperature, observe the Average Total Fuel Trim parameter with a scan tool. The Average Total Fuel Trim

should be between -22 to +23 percent.

瀚慖f not within the specified range, inspect for the following conditions:

* A mass air flow sensor signal that is skewed. If the Short Term Fuel Trim parameter changes greater than 20 percent when the MAF

sensor is disconnected, refer to DTC P0101 (LAU) (See: P Code Charts/P0101)DTC P0101 (LF1) (See: P Code Charts/P0101).

* A collapsed air intake duct

* A restricted air filter element-Refer to Air Cleaner Element Replacement (LF1) (See: Engine, Cooling and Exhaust/Engine/Tune-up and

Engine Performance Checks/Air Cleaner Housing/Air Filter Element/Service and Repair)Air Cleaner Element Replacement (LAU) (See:

Engine, Cooling and Exhaust/Engine/Tune-up and Engine Performance Checks/Air Cleaner Housing/Air Filter Element/Service and

Repair).

* The MAF sensor for foreign objects.

* Excessive fuel in the crankcase-Change the oil as necessary.

* Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool) (See: Powertrain Management/Fuel Delivery and

Air Induction/Fuel/Testing and Inspection/Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool))Alcohol/Contaminants-in-Fuel

Diagnosis (Without Special Tool) (See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Component

Tests and General Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool)) and Fuel System Cleaning (See:

Powertrain Management/Fuel Delivery and Air Induction/Service and Repair).

* The engine control module grounds for being clean, tight, and in the correct locations

* Rich injectors-Refer to Fuel Injector Solenoid Coil Test (LAU) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel

Injector/Testing and Inspection/Fuel Injector Solenoid Coil Test)Fuel Injector Solenoid Coil Test (LF1, LFW) (See: Powertrain

Management/Fuel Delivery and Air Induction/Fuel Injector/Testing and Inspection/Fuel Injector Solenoid Coil Test).

* Restricted exhaust system-Refer to Symptoms - Engine Exhaust (See: Engine, Cooling and Exhaust/Exhaust System/Testing and

Inspection/Symptoms - Engine Exhaust).

* An engine mechanical condition-Refer to Symptoms - Engine Mechanical (See: Engine, Cooling and Exhaust/Engine/Testing and

Inspection/Symptom Related Diagnostic Procedures/Symptoms - Engine Mechanical).

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.

Repair Instructions

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

P2187

DTC P2177 or P2187

Diagnostic Instructions

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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1576

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. Perform the Transmission Fluid Level and Condition Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing

and Inspection/Symptom Related Diagnostic Procedures/AF40-6 - Automatic Transmission/Transmission Fluid Level and Condition Check)

to verify correct fluid level.

2. Engine idling at operating temperature, observe the scan tool Transmission Fluid Temperature parameter. The reading should be between -40

to +215掳C (-40 to +488掳F) and change.

3. Operate the vehicle at about 60 km/h (37 MPH) for 10 min. Verify the scan tool Transmission Fluid Temperature parameter varies by more

than 2掳C (3.5掳F) to verify that the sensor is not stuck.

Circuit/System Testing

Operate the vehicle within the conditions for running and setting 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.

Component Testing

Static Test

1. Ignition OFF, remove the K71 Transmission Control Module.

2. Ignition OFF, test for infinite resistance between the low reference circuit terminal 7 X2 and ground.

瀚慖f less than the specified range, replace the wiring harness.

3. Ignition OFF, test for infinite resistance between the signal circuit terminal 8 X2 and ground.

瀚慖f less than the specified range, replace the wiring harness.

4. Test for infinite resistance between each terminal and the low reference circuit terminal 7 X2 and also to the signal circuit terminal 8 X2.

瀚慖f less than the specified range, replace the wiring harness.

5. Test for the resistance between the B13 Automatic Transmission Fluid Temperature Sensor signal circuit terminal 7 X2 and the low reference

circuit terminal 8 X2. Refer to Transmission Fluid Temperature Sensor Specifications (See: Transmission and Drivetrain/Automatic

Transmission/Transaxle/Specifications/Pressure, Vacuum and Temperature Specifications) for the resistance values.

瀚慖f not within the specified range, replace the wiring harness.

6. If the circuit test normal, replace the K71 Transmission Control Module.

Repair Instructions

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

* Wiring harness-Refer to Automatic Transmission Wiring Harness Replacement (See: Transmission and Drivetrain/Automatic

Transmission/Transaxle/Wiring Harness/Service and Repair) for replacement.

* TCM-Refer to Control Module References (See: Testing and Inspection/Programming and Relearning) for replacement, setup, and

programming.

* Perform the Transmission Adaptive Functions (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and

Operation/AF40-6 - Automatic Transmission/Transmission Adaptive Functions).

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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1420

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

Special Tools

DT-47825-20 Adapter Harness

Circuit/System Verification

1. Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6-15.0

volts.

瀚慖f the voltage is not within the specified range, or the charge indicator light is ON, refer to Charging System Test (See: Starting and

Charging/Testing and Inspection/Component Tests and General Diagnostics/Charging System Test).

2. Observe the scan tool TCM Ignition Voltage parameter. The reading should be between 12.6-15.0 volts.

3. 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 20-way harness connector at the transmission.

2. Connect the DT-47825-20 to the 20-way transmission harness connector.

3. Test for less than 10 ohms between the ground circuit terminals listed below and ground.

* Terminal 1

* Terminal 18

瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.

4. Ignition ON, verify that a test lamp illuminates between the ignition and B+ circuit terminals listed below and ground.

* Terminal 10

* Terminal 13

* Terminal 15

瀚慖f the test lamp does not illuminate, test the affected ignition or B+ circuit for a short to ground or an open/high resistance.

5. If all circuits test normal, replace the control solenoid valve assembly.

Repair Instructions

Important:

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

Inspection/Programming and Relearning) following all transmission related repairs.

* Before replacing the TCM, 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/6T70/6T75 - Automatic Transmission/Control Solenoid Valve and Transmission Control Module Assembly Inspection).

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

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

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 745

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 Testing

1. Inspect the trailer rear fog lamp bulb for an open or shorted filament.

瀚慖f the bulb is inoperable, replace the bulb.

2. Park lamp switch OFF, clear the DTC, test the trailer rear fog lamp circuit for a short to voltage, short to ground, an open, or high resistance.

瀚慖f all circuits/connections test normal, replace the XBCM.

Repair Instructions

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

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

Gasoline With LY6, or Diesel

DTC B3894 (Gasoline With LY6, or Diesel)

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 Descriptor

DTC B3894 5A

- Stop Lamp Switch Circuit Plausibility Failure

Circuit/System Description

The brake switch is hard wired to the trailer brake control module (TBCM). The body control module (BCM) sends a brake switch status serial data

message to the trailer brake control module. The trailer brake control module compares the states of the brake switch signal to the serial data

message after a master cylinder brake pressure sensor threshold is exceeded. If the brake switch signal and the serial data message are not in

agreement or if the serial data message is not valid, a DTC will set and the trailer brake control system will be disabled.

Conditions for Running the DTC

* Battery voltage is 9.5-17 V.

* The module initialization has taken place.

* The master cylinder brake pressure exceeds threshold

Conditions for Setting the DTC

* The brake switch serial data message is not valid.

* The actual brake switch input to the trailer brake control module, and the serial data information for the brake switch do not match.

Action Taken When the DTC Sets

* The trailer brake control will be disabled for the remainder of the ignition cycle.

* The driver information center will display Service Trailer Brake System.

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 720

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, command the appropriate actuator in both directions with a scan tool. The scan tool door position parameter reading should be

between 3 and 253 counts.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate actuator.

2. Test for less than 10 ohms between the low reference circuit terminal 7 and ground.

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

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 10 and ground.

瀚慖f less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance.

瀚慖f greater than the specified range, test the 5-volt reference circuit for a short to voltage.

4. Verify the appropriate scan tool parameter is greater than 250 counts.

瀚慖f greater than the specified range, test the signal circuit terminal 9 for a short to ground.

5. Install a 3-amp fused jumper wire between the signal circuit terminal 9 and the low reference circuit terminal. Verify the appropriate scan

tool parameter is less than 4 counts.

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

6. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

7. Install a DMM between the actuator control circuit terminal 6 and ground. While monitoring the DMM, use the scan tool to command the

appropriate actuator from one direction to the other. The voltage on the control circuit should move from 0 volts in one direction to 5 volts in

the other direction and 2.5 volts in the at rest state.

瀚慖f the voltage does not change, test the control circuit for an open, short to voltage or short to ground. If circuit tests normal replace the

HVAC control module.

8. If all circuits test normal, replace the actuator.

Repair Instructions

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

* Air Inlet Valve Actuator Replacement (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Air Inlet Valve Actuator Replacement)

* Mode Valve Actuator Replacement (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Mode Valve Actuator Replacement)

* Temperature Valve Actuator Replacement - Left Side (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and

Repair/HVAC - Automatic/Temperature Valve Actuator Replacement - Left Side)

* Temperature Valve Actuator Replacement - Right Side (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service

and Repair/HVAC - Automatic/Temperature Valve Actuator Replacement - Right Side)

* Auxiliary Temperature Valve Actuator Replacement (Behr) (See: Heating and Air Conditioning/Air Door/Air Door Actuator /

Motor/Service and Repair/HVAC - Automatic/Auxiliary Temperature Valve Actuator Replacement (Behr))Auxiliary Temperature Valve

Actuator Replacement (Delphi) (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Auxiliary Temperature Valve Actuator Replacement (Delphi))

* Auxiliary Mode Valve Actuator Replacement (Behr) (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and

Repair/HVAC - Automatic/Auxiliary Mode Valve Actuator Replacement (Behr))Auxiliary Mode Valve Actuator Replacement (Delphi) (

See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC - Automatic/Auxiliary Mode Valve

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 669

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

Important: When using this diagnostic, more than one vehicle key is required to ensure proper diagnosis. If more than one key is not

available at the time of service, contact the customer and ask if any other keys can be provided for service. If unavailable, a new second

key can be created.

1. Inspect all available vehicle keys that they are correct vehicle keys.

瀚慖f not a correct vehicle key, replace the key.

2. While viewing the scan tool TDM Transponder Key parameter, turn ON the ignition with each of the available vehicle keys. The parameter

should read Present with all available keys.

瀚慖f only one key results in the parameter reading Not Present, replace the appropriate key.

瀚慖f all available keys result in the parameter reading Not Present, replace the TDM.

Repair Instructions

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

* Replacing Keys (North America except Canada) (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Service and

Repair/Replacing Keys (North America Except Canada))

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

B3060

DTC B3060

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 B3060 00

- Unprogrammed Transponder Identification Code Received

Circuit/System Description

When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is

energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value,

which is received by the theft deterrent module (TDM). The TDM then compares this value to a value stored in memory. This stored value is the

learned key code. If the value is correct, the TDM will send the prerelease password via the serial data circuit to the engine control module (ECM).

If the transponder value does not match the learned key code or a transponder value is not received, the TDM will send the start disable password to

the ECM.

Conditions for Running the DTC

Ignition is in the Accessory or Run position.

Conditions for Setting the DTC

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 624

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 Testing

1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.

2. Connect a test lamp between the control circuit terminal 9 and ground.

3. Ignition ON, command the Backup Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the

commanded states.

瀚慖f the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

瀚慖f the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the BCM.

4. Ignition OFF, connect the harness connector at the inside rearview mirror. Disconnect the X5 harness connector at the underhood fuse block.

5. Connect a test lamp between the control circuit terminal H8 and ground.

6. Ignition ON, command the Backup Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the

commanded states.

瀚慖f the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

瀚慖f the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the BCM.

7. If all circuits test normal, replace the underhood fuse block.

Repair Instructions

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

* Underhood Electrical Center or Junction Block Replacement (See: Maintenance/Fuses and Circuit Breakers/Fuse Block/Service and

Repair/Removal and Replacement/Underhood Electrical Center or Junction Block Replacement)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM, inside rearview mirror, and rearview

camera module replacement, setup, and programming

B2555

DTC B2555

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 B2555 01

- Passenger Compartment Lamp Control Circuit Short to Battery

DTC B2555 02

- Passenger Compartment Lamp Control Circuit Short to Ground

Diagnostic Fault Information

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 355

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

Clear all DTCs and operate the integrated switches at each door control module within the Conditions for Running the DTC. The DTC should not

set.

If the DTC sets, replace the appropriate door switch.

Repair Instructions

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

Control Module References (See: Testing and Inspection/Programming and Relearning) for DDS and PDS replacement, setup, and programming

HVAC - Automatic

DTC B1023

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 B1023 05

- Integral Switch Performance Short to Ground

DTC B1023 06

- Integral Switch Performance Short to Battery or Open

DTC B1023 61

- Integral Switch Performance Signal Invalid

Circuit/System Description

This DTC is not associated with any wiring. It is an internal fault inside the HVAC control module for a stuck or shorted control button.

Conditions for Running the DTC

Battery voltage is between 9-16 volts and data link communications operate normally.

Conditions for Setting the DTC

The HVAC control module has internal fault inside the HVAC control module for a stuck or shorted control button.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.

* A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Circuit/System Verification

1. Reprogram the HVAC control module that set DTC B1023. The module should successfully reprogram.

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 923

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 923

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.

Special Tools

* EL-49741 - 9 V+ Power Source Harness

* EL-49742 - Battery Voltage B+ and Ground Source Harness

* J 35616 - GM-Approved Terminal Test Kit

Circuit/System Verification

1. Key ON, engine OFF.

2. Connect a scan tool.

3. Using the TCSCS, select each transfer case mode/range while monitoring the Rotational Position Sensor parameter and the Incremental

Position Sensor parameter on the scan tool, The Rotational Position Sensor parameter and the Incremental Position Sensor parameter should

track within 5 degrees of each other.

Circuit/System Testing

Note: When test probing harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 - Kit.

Use of an improper test probe may deform the terminal, resulting in intermittent open conditions.

1. Key OFF. Disconnect the X1 connector from the transfer case two/four wheel drive actuator position sensor also known as the rotational

position sensor (RPS).

2. Key ON, engine OFF.

3. Using the GY probe J 35616-2A, test for 4.8-5.2 V between the 5-volt reference circuit, RPS X1 pin B and a good ground (the ground

terminal of the EL-49742 - harness, black terminal).

瀚慖f the voltage is less than the specified range, test the affected circuit for an open/high resistance or short to ground. If all circuits and

connections test normal, test the TCCM for proper operation.

瀚慖f the voltage is greater than the specified range, test the affected circuit for a short to voltage. If all circuits and connections test normal,

test the TCCM for proper operation.

4. Using the GY probes J 35616-2A, test for 4.8-5.2 V between the 5-volt reference circuit, RPS X1 pin B and the low reference circuit, RPS

X1 pin A.

瀚慖f the voltage is less than the specified range, test the low reference circuit for an open/high resistance. If all circuits and connections test

normal, test the TCCM for proper operation.

瀚慖f the voltage is greater than the specified range, test the low reference circuit for a short to voltage. If all circuits and connections test

normal, test the TCCM for proper operation.

5. Using the GY probes J 35616-2A, test for 4.5-5.0 V between the rotary position sensor signal circuit, RPS X1 pin C and a good ground.

瀚慖f the voltage is less than the specified range, test the rotary position sensor signal circuit for an open/high resistance or short to ground. If

all circuits and connections test normal, test the TCCM for proper operation.

瀚慖f the voltage is greater than the specified range, test the rotary position sensor signal circuit for a short to voltage. If all circuits and

connections test normal, test the TCCM for proper operation.

6. Using the GY probe J 35616-2A, test for greater than 500 ohm between the low reference circuit, RPS X1 pin A and all other pins of the RPS

X1.

瀚慖f the resistance is less than the specified range, test the affected circuits for a shorted together condition. If all circuits and connections

test normal, test the TCCM for proper operation.

7. Using the GY probe J 35616-2A, test for greater than 500 ohm between the 5-volt reference circuit, RPS X1 pin B and all other pins of the

RPS X1.

瀚慖f the resistance is less than the specified range, test the affected circuits for a shorted together condition. If all circuits and connections

test normal, test the TCCM for proper operation.

8. Key OFF. Disconnect TCCM connector X2.

9. Using the GY probe J 35616-2A, test for greater than 10 ohm between the low reference circuit, TCSCS X2 pin 9 and all other pins of the

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2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 308

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, command the appropriate actuator in both directions with a scan tool. The scan tool door position parameter reading should be

between 3 and 253 counts.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate actuator.

2. Test for less than 10 ohms between the low reference circuit terminal 7 and ground.

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

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 10 and ground.

瀚慖f less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance.

瀚慖f greater than the specified range, test the 5-volt reference circuit for a short to voltage.

4. Verify the appropriate scan tool parameter is greater than 250 counts.

瀚慖f greater than the specified range, test the signal circuit terminal 9 for a short to ground.

5. Install a 3-amp fused jumper wire between the signal circuit terminal 9 and the low reference circuit terminal. Verify the appropriate scan

tool parameter is less than 4 counts.

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

6. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

7. Install a DMM between the actuator control circuit terminal 6 and ground. While monitoring the DMM, use the scan tool to command the

appropriate actuator from one direction to the other. The voltage on the control circuit should move from 0 volts in one direction to 5 volts in

the other direction and 2.5 volts in the at rest state.

瀚慖f the voltage does not change, test the control circuit for an open, short to voltage or short to ground. If circuit tests normal replace the

HVAC control module.

8. If all circuits test normal, replace the actuator.

Repair Instructions

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

* Air Inlet Valve Actuator Replacement (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Air Inlet Valve Actuator Replacement)

* Mode Valve Actuator Replacement (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Mode Valve Actuator Replacement)

* Temperature Valve Actuator Replacement - Left Side (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and

Repair/HVAC - Automatic/Temperature Valve Actuator Replacement - Left Side)

* Temperature Valve Actuator Replacement - Right Side (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service

and Repair/HVAC - Automatic/Temperature Valve Actuator Replacement - Right Side)

* Auxiliary Temperature Valve Actuator Replacement (Behr) (See: Heating and Air Conditioning/Air Door/Air Door Actuator /

Motor/Service and Repair/HVAC - Automatic/Auxiliary Temperature Valve Actuator Replacement (Behr))Auxiliary Temperature Valve

Actuator Replacement (Delphi) (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Auxiliary Temperature Valve Actuator Replacement (Delphi))

* Auxiliary Mode Valve Actuator Replacement (Behr) (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and

Repair/HVAC - Automatic/Auxiliary Mode Valve Actuator Replacement (Behr))Auxiliary Mode Valve Actuator Replacement (Delphi) (

See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC - Automatic/Auxiliary Mode Valve

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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 2048

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 References

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

Circuit/System Testing

Note: If more than one module is not communicating use Data Communication Schematics (See: Powertrain Management/Computers and

Control Systems/Information Bus/Diagrams/Electrical Diagrams) to determine which module is closest to the DLC. Start diagnostics with that

module.

Terminal and connector identifiers will be different depending on the individual module being tested. Use Schematic Reference and Connector End

View Reference to determine which connector and terminal to access.

1. Using the DTC Descriptor and Diagnostic Aids, determine the module that is not communicating that should be tested.

2. Ignition OFF, disconnect the harness connector of the module that is not communicating.

3. Test for less than 2 ohms between the module ground circuits and ground.

瀚慖f greater than specified range, test the ground circuit for an open/high resistance.

Note: Only the high speed GMLAN modules have a wired serial data wake up circuit. Refer to the module schematics to identify which

modules have a wake up circuit. If the module that is not communicating does not have a serial data wake up circuit, proceed to step 5.

4. Ignition ON, verify that a test lamp illuminates between the high speed GMLAN serial data wake up circuit OR the accessory wake up serial

data circuit and ground.

瀚慖f the test lamp does not illuminate, test the circuit for an open/high resistance. If the circuits test normal, replace the BCM.

5. Ignition ON, verify that a test lamp illuminates between all B+ circuits and ground.

瀚慖f the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit fuse is open, also test

the positive voltage outputs of the module for a short to ground. If the circuits test normal, replace the appropriate module.

6. Verify that a test lamp illuminates between all ignition voltage circuits and ground.

瀚慖f the test lamp does not illuminate, test the ignition voltage circuits for a short to ground or an open/high resistance. If the circuit fuse is

open, also test the positive voltage outputs of the module for a short to ground. If the circuits test normal, replace the appropriate module.

7. Test for less than 1 Ohms in the GMLAN serial data circuits between the non-communicating module and the module that displays the DTC.

瀚慖f greater than specified range, test the GMLAN serial data circuits for open/high resistance.

8. If all circuits test normal, replace the module that is not communicating.

Repair Instructions

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

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

Procedures/Wiring Repairs/GMLAN Wiring Repairs)

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

U2199

DTC U2105-U2199

Diagnostic Instructions

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

Check - Vehicle) prior to using the 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.

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 286

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 286

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, command the appropriate actuator in both directions with a scan tool. The scan tool door position parameter reading should be

between 3 and 253 counts.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate actuator.

2. Test for less than 10 ohms between the low reference circuit terminal 7 and ground.

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

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 10 and ground.

瀚慖f less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance.

瀚慖f greater than the specified range, test the 5-volt reference circuit for a short to voltage.

4. Verify the appropriate scan tool parameter is greater than 250 counts.

瀚慖f greater than the specified range, test the signal circuit terminal 9 for a short to ground.

5. Install a 3-amp fused jumper wire between the signal circuit terminal 9 and the low reference circuit terminal. Verify the appropriate scan

tool parameter is less than 4 counts.

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

6. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

瀚慖f the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.

7. Install a DMM between the actuator control circuit terminal 6 and ground. While monitoring the DMM, use the scan tool to command the

appropriate actuator from one direction to the other. The voltage on the control circuit should move from 0 volts in one direction to 5 volts in

the other direction and 2.5 volts in the at rest state.

瀚慖f the voltage does not change, test the control circuit for an open, short to voltage or short to ground. If circuit tests normal replace the

HVAC control module.

8. If all circuits test normal, replace the actuator.

Repair Instructions

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

* Air Inlet Valve Actuator Replacement (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Air Inlet Valve Actuator Replacement)

* Mode Valve Actuator Replacement (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Mode Valve Actuator Replacement)

* Temperature Valve Actuator Replacement - Left Side (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and

Repair/HVAC - Automatic/Temperature Valve Actuator Replacement - Left Side)

* Temperature Valve Actuator Replacement - Right Side (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service

and Repair/HVAC - Automatic/Temperature Valve Actuator Replacement - Right Side)

* Auxiliary Temperature Valve Actuator Replacement (Behr) (See: Heating and Air Conditioning/Air Door/Air Door Actuator /

Motor/Service and Repair/HVAC - Automatic/Auxiliary Temperature Valve Actuator Replacement (Behr))Auxiliary Temperature Valve

Actuator Replacement (Delphi) (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC -

Automatic/Auxiliary Temperature Valve Actuator Replacement (Delphi))

* Auxiliary Mode Valve Actuator Replacement (Behr) (See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and

Repair/HVAC - Automatic/Auxiliary Mode Valve Actuator Replacement (Behr))Auxiliary Mode Valve Actuator Replacement (Delphi) (

See: Heating and Air Conditioning/Air Door/Air Door Actuator / Motor/Service and Repair/HVAC - Automatic/Auxiliary Mode Valve

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 807

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 807

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)

Circuit/System Testing

Verify that DTC U0074 is not set.

If the DTC is set, refer to DTC U0074 (See: U Code Charts/U0074)

Antilock Brake System - Non-Hybrid Less than 3900 kg (8600 lb) GVW

DTC C0035-C0050

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 C0035 00

- Left Front Wheel Speed Sensor Circuit

DTC C0035 5A

- Left Front Wheel Speed Sensor Circuit Plausibility Failure

DTC C0040 00

- Right Front Wheel Speed Sensor Circuit

DTC C0040 5A

- Right Front Wheel Speed Sensor Circuit Plausibility Failure

DTC C0045 00

- Left Rear Wheel Speed Sensor Circuit

DTC C0045 5A

- Left Rear Wheel Speed Sensor Circuit Plausibility Failure

DTC C0050 00

- Right Rear Wheel Speed Sensor Circuit

DTC C0050 5A

- Right Rear Wheel Speed Sensor Circuit Plausibility Failure

Diagnostic Fault Information

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 788

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 788

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 Testing

1. Inspect the trailer rear fog lamp bulb for an open or shorted filament.

瀚慖f the bulb is inoperable, replace the bulb.

2. Park lamp switch OFF, clear the DTC, test the trailer rear fog lamp circuit for a short to voltage, short to ground, an open, or high resistance.

瀚慖f all circuits/connections test normal, replace the XBCM.

Repair Instructions

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

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

Gasoline With LY6, or Diesel

DTC B3894 (Gasoline With LY6, or Diesel)

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 Descriptor

DTC B3894 5A

- Stop Lamp Switch Circuit Plausibility Failure

Circuit/System Description

The brake switch is hard wired to the trailer brake control module (TBCM). The body control module (BCM) sends a brake switch status serial data

message to the trailer brake control module. The trailer brake control module compares the states of the brake switch signal to the serial data

message after a master cylinder brake pressure sensor threshold is exceeded. If the brake switch signal and the serial data message are not in

agreement or if the serial data message is not valid, a DTC will set and the trailer brake control system will be disabled.

Conditions for Running the DTC

* Battery voltage is 9.5-17 V.

* The module initialization has taken place.

* The master cylinder brake pressure exceeds threshold

Conditions for Setting the DTC

* The brake switch serial data message is not valid.

* The actual brake switch input to the trailer brake control module, and the serial data information for the brake switch do not match.

Action Taken When the DTC Sets

* The trailer brake control will be disabled for the remainder of the ignition cycle.

* The driver information center will display Service Trailer Brake System.