2010 Cadillac CTS Sedan AWD V6-3.0L Page 1846
瀚慖f less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal,
replace the ECM.
瀚慖f greater than the specified range, test the 5-volt 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. 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.
6. Install a 3 A fused jumper wire between TP sensor 1 signal circuit terminal D and the 5-volt 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.
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 (LF1) (See: Powertrain Management/Fuel Delivery and Air Induction/Throttle Body/Service and
Repair/Removal and Replacement)Throttle Body Assembly Replacement (LLT) (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 ECM replacement, setup, and programming
P2138
DTC P2122, P2123, P2127, P2128, or P2138 (LF1)
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 P2122
- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage
DTC P2123
- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage
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
