2010 Cadillac CTS Sedan AWD V6-3.0L Page 1839

2010 Cadillac CTS Sedan AWD V6-3.0L Page 1839

The APP Sensor 1 and 2 Agree/Disagree parameter should display Agree.

4. Observe the DTC information with a scan tool. DTCs P2122, P2123, P2127, P2128, or P2138 should not set.

5. 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 assembly.

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

* Low reference circuit terminal A

* Low reference circuit terminal D

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

tests normal, replace the ECM.

3. Ignition ON, test for 4.8-5.2 V between both 5-volt reference circuit terminals listed below and ground.

* 5 volt reference circuit terminal C

* 5 volt reference circuit terminal F

瀚慖f less than the specified range, test the appropriate 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. Verify the appropriate APP sensor voltage parameter is at 0 V.

瀚慖f greater than the specified range, test the appropriate signal circuit terminal listed below for a short to voltage. If the circuit tests normal,

replace the ECM.

* APP sensor 1 signal circuit terminal E

* APP sensor 2 signal circuit terminal B

5. Install a 3 A fused jumper wire between the appropriate signal circuit listed below and the 5-volt reference circuit terminal C. Verify the

appropriate APP sensor voltage parameter is greater than 4.8 V.

* APP sensor 1 signal circuit terminal E

* APP sensor 2 signal circuit terminal B

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

normal, replace the ECM.

6. If all circuits test normal, replace the accelerator pedal assembly.

Repair Instructions

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

* 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 ECM replacement, setup, and programming

P2128

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