2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1781
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 TP sensor 1 and 2 voltage parameters. Both parameters should be between 1.0-4.0 V and change with accelerator pedal input.
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.
3. Perform the Throttle Sweep Test while observing the TP Sensor 1 and 2 Agree/Disagree parameter with a scan tool. The TP Sensor 1 and 2
Agree/Disagree parameter should display Agree.
4. 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.
5. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0120 or P0220 are not the only TP sensor DTCs set.
瀚慖f DTC P0120 or P0220 are the only DTCs set, replace the ECM.
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
1. Ignition OFF, disconnect the harness connector at the throttle body assembly.
2. 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 low reference circuit terminal C and ground.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
3. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal E and ground.
瀚慖f less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests 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 tests normal, replace the ECM.
4. Test for less than 1 V between the TP sensor 1 signal circuit terminal D and ground.
瀚慖f greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
5. Install a 3 A fused jumper wire between TP sensor 1 signal circuit terminal D and the 5 V reference circuit terminal E. Verify the scan tool
TP 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 tests normal, replace
the ECM.
6. Test for 4.8-5.2 V between the TP sensor 2 signal circuit terminal F and ground.
瀚慖f less than specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the
ECM.
瀚慖f greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
7. If all circuits test normal, test or replace the throttle body assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* 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
P0128
DTC P0128 (Without L96)
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.
