2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1743
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 38522 Variable Speed Generator
Circuit/System Verification
1. Verify that DTC P0641 or P0651 is not set.
瀚慖f any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) for DTC P0641 or P0651 for further diagnosis.
2. Verify restrictions do not exist in the exhaust system. Refer to Restricted Exhaust (See: Engine, Cooling and Exhaust/Exhaust
System/Testing and Inspection/Restricted Exhaust).
3. Engine idling, observe the scan tool MAF Sensor parameter. The reading should be between 2,000-3,900 Hz depending on the ECT.
4. A wide open throttle (WOT) acceleration from a stop should cause the MAF Sensor parameter on the scan tool to increase rapidly. This
increase should be from 4-9 g/s at idle to greater than 180 g/s at the time of the 1-2 shift.
5. Use the scan tool and compare the MAF Sensor parameter to a known good vehicle under various operating conditions.
6. Ignition ON, observe the MAP sensor pressure parameter and compare to the Altitude Versus Barometric Pressure (See: Powertrain
Management/Computers and Control Systems/Specifications/Altitude Versus Barometric Pressure) table. The MAP sensor reading should be
within the specified range.
瀚慖f the MAP sensor pressure is not within the specified range, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic
Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) for DTC P0106 for further diagnosis.
7. 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. Inspect for the following conditions:
* A dirty or deteriorating air filter element
* A leaking, loose, or cracked PCV pipe or seal
* A loose or disconnected charge air cooler hose or pipe
* A restricted or collapsed air intake duct
* A misaligned or damaged air intake duct
* Any objects blocking the air inlet probe of the MAF/IAT sensor
* Any contamination or debris on the sensing elements in the probe of the MAF/IAT sensor
* A cracked or damaged MAF sensor housing
* Any water intrusion in the induction system
* Any snow or ice build-up at the air cleaner, MAF or MAP sensors in cold climates
* An intake manifold leak
* A MAP sensor seal that is leaking, missing, or damaged
* An Intake Manifold Resonator with a leaking seal, or a cracked or broken housing
瀚慖f you find any of the above conditions, repair as necessary.
2. Ignition OFF, disconnect the harness connector at the MAF/IAT sensor.
3. Ignition OFF, all vehicle systems OFF, this may take up to 2 min, test for less than 5 ohm between the ground circuit terminal E and ground.
瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.
4. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 ohm
between the IAT sensor low reference circuit terminal A and ground.
瀚慖f greater than the specified range, test the IAT sensor low reference circuit for an open/high resistance. If the circuit tests normal, replace
the ECM.
5. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal D 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.
