18047/P1639/005689 - Accelerator Position Sensor 1/2 (G79/G185): Implausible Signal
Possible Symptoms

    Malfunction Indicator Light (MIL) ON
    Reduced Engine Output

Possible Causes

    Wiring and/or connections faulty
    Faulty ECM
    Faulty Accelerator Pedal

Possible Solutions

    Check Measuring Block Readings for Accelerator Pedal
    Check Voltage Signals from ECM to Throttle Pedal (see factory repair manual)
    Check Wiring and Connectors from ECM to Accelerator Pedal

Special Notes

    There are 2 sensors in the accelerator pedal, both should increase in the same direction as the accelerator is pressed but they have different scales. This means one counts from 0 to 100, while the other one counts from 0 to 50.

    Accelerator Position Sensor faults can be caused by issues with the Oxygen Sensor(s) and it's wiring. Please verify this BEFORE replacing the ECM or Accelerator Pedal. Accelerator Pedal failure is very rare.


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