Diagnostic Test

DTC IS ACTIVE
NOTE: If any Sensor reference or supply voltage DTCs are present, perform the applicable diagnostic procedure before continuing with this test.

NOTE: The APP Sensor is a device that contains 2 separate potentiometer type sensors. Each sensor has its own 5-volt supply circuit, sensor ground circuit and signal circuit. The APP Sensor no longer incorporates a low-idle switch.

NOTE: The APP Sensor 2 signal should always be approximately 1/2 the voltage of the APP Sensor 1 signal.
1. Ignition on, engine not running.
2. With the scan tool, Clear DTCs in the Engine Control Module (ECM).
3. Test drive the vehicle.
4. With the scan tool, select View DTCs.
  Is the status Active for this DTC?
  
  Yes
  - Go to step 2
  No
  - Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. See DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure
ACCELERATOR PEDAL POSITION SENSOR CIRCUIT OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the APP Sensor harness connector.
3. Disconnect the ECM harness connector.
4. Measure the resistance of the Accelerator Pedal Position Sensor No. 1 5 Volt Supply circuit between the Accelerator Pedal Position Sensor harness connector and the Engine Control Module (ECM) harness connector.
5. Measure the resistance of the Accelerator Pedal Position Sensor No. 1 Signal circuit between the Accelerator Pedal Position Sensor harness connector and the Engine Control Module (ECM) harness connector.
6. Measure the resistance of the Accelerator Pedal Position Sensor No. 1 Sensor Ground circuit between the Accelerator Pedal Position Sensor harness connector and the Engine Control Module (ECM) harness connector.
7. Measure the resistance of the Accelerator Pedal Position Sensor No. 2 5 Volt Supply circuit between the Accelerator Pedal Position Sensor harness connector and the Engine Control Module (ECM) harness connector.
8. Measure the resistance of the Accelerator Pedal Position Sensor No. 2 Signal circuit between the Accelerator Pedal Position Sensor harness connector and the Engine Control Module (ECM) harness connector.
9. Measure the resistance of the Accelerator Pedal Position Sensor No. 2 Sensor Ground circuit between the Accelerator Pedal Position Sensor harness connector and the Engine Control Module (ECM) harness connector.
  Is the resistance below 10.0 ohms for each of the circuits?
  
  Yes
  - Replace the Accelerator Pedal Position Sensor.
  No
  - Repair the circuit for an open circuit or high resistance.
  - Perform the ECM Verification Test. See DTC-Based Diagnostics/MODULE, Engine Control (ECM) - Standard Procedure .