*CHECKING THE ACCELERATOR PEDAL POSITION SENSOR CALIBRATION
For a complete wiring diagram Refer to Section 8W
Theory of Operation
The Accelerator Pedal Position Sensor (APP) 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 2 signal should always be approximately 1/2 the voltage of the APP Sensor 1 signal.
| Possible Causes |
| APP SENSOR OPERATION |
| APP SENSOR CIRCUIT 1 HIGH RESISTANCE |
| APP SENSOR CIRCUIT 2 HIGH RESISTANCE |
Diagnostic Test
1.APP SENSOR IDLE VOLTAGE
Is the voltage between 0.42 and 0.51 volt for sensor 1 and 0.19 and 0.28 volt for sensor 2?
Yes
- Go To2
No
- Check the wiring and connectors related to the Accelerator Pedal Position Sensor. If OK, replace the Accelerator Pedal Position Sensor.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
2.APP SENSOR
Did the voltage for both sensors increase smoothly with pedal travel?
Yes
- Go To3
No
- Replace the Accelerator Pedal Position Sensor in accordance with the Service Information.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
3.APP SENSOR WIDE OPEN THROTTLE VOLTAGE
Is the voltage between 4.45 and 4.75 volts for #1 and 2.15 and 2.45 volts for #2?
Yes
- Test Complete.
No
- Check the wiring and connectors related to the APP Sensor. If OK, replace the Accelerator Pedal Position Sensor.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).