NGC

P2123-ACCELERATOR PEDAL POSITION SENSOR 1 CIRCUIT HIGH





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.

- Set Condition:
The PCM detects that the APP Sensor 1 input voltage is above the maximum acceptable value.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE

NOTE: Diagnose and repair any system voltage or sensor supply voltage DTCs before continuing with this test.

Start the engine and allow it to reach normal operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

2. (F856) 5 VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE




Turn the ignition off.
Disconnect the Accelerator Pedal Position Sensor connector.
Disconnect the Powertrain Control Module (PCM) connector.
Turn the ignition on.
Measure the voltage of the (F856) 5 Volt Supply circuit in the Accelerator Pedal Position Sensor harness connector.
Is there any voltage present?

Yes

- Repair the (F856) 5 Volt Supply circuit for a short to voltage.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 3

3. (K23) APP SIGNAL 1 CIRCUIT SHORTED TO VOLTAGE




Measure the voltage of the (K23) APP Signal 1 circuit in the Accelerator Pedal Position Sensor harness connector.
Is there any voltage present?

Yes

- Repair the (K23) APP Signal 1 circuit for a short to voltage.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 4

4. (K23) APP SIGNAL 1 CIRCUIT SHORTED TO THE (F856) 5 VOLT SUPPLY CIRCUIT




Measure the resistance between the (K23) APP Signal 1 circuit and the (F856) 5 Volt Supply in the Accelerator Pedal Position Sensor harness connector.
Is the resistance below 100 ohms?

Yes

- Repair the (K23) APP Signal 1 circuit for a short to the (F856) 5 Volt Supply circuit.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 5

5. (K23) APP SIGNAL 1 CIRCUIT SHORTED TO THE (K858) 5 VOLT SUPPLY CIRCUIT




Measure the resistance between the (K23) APP Signal 1 circuit and the (K858) 5 Volt Supply in the Accelerator Pedal Position Sensor harness connector.
Is the resistance below 100 ohms?

Yes

- Repair the (K23) APP Signal 1 circuit for a short to the (K858) 5 Volt Supply circuit.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 6

6. (K23) APP SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE
Turn the ignition off.
Measure the resistance of the (K23) APP Signal 1 between the Accelerator Pedal Position Sensor harness connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 ohms?

Yes

- Go to 7

No

- Repair the (K23) APP Signal 1 for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

7. (K167) SENSOR GROUND CIRCUIT OPEN OR HIGH RESISTANCE
Measure the resistance of the (K167) Sensor Ground circuit between the Accelerator Pedal Position Sensor harness connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 ohms?

Yes

- Go to 8

No

- Repair the (K167) Sensor Ground circuit for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

8. ACCELERATOR PEDAL POSITION SENSOR




Turn the ignition off.
Connect the Powertrain Control Module (PCM) connector.
Connect a jumper wire between the (K167) Sensor Ground circuit and the (K23) APP Signal 1 circuit in the Accelerator Pedal Position Sensor harness connector.
Turn the ignition on.
With the scan tool, read the Accelerator Pedal Position Sensor signal voltage.
Is the voltage below 1.0 volt with the jumper wire in place?

Yes

- Replace the Accelerator Pedal Position Sensor.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Go to 9

9. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Accelerator Pedal Position Sensor and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test Ver. 1Powertrain Verification Test.