Circuit DescriptionSensor supply 4 of the engine control module (ECM) provides a 5 VDC supply to the accelerator pedal position sensor.

Component LocationThe accelerator pedal or lever position sensor is mounted to the accelerator pedal assembly. Refer to the OEM service manual.

Conditions for Running the DiagnosticsThis diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the sensor supply 4 signal voltage was less than 4.75-VDC for more than 1 second.

Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.The engine will only idle.Conditions for Clearing the Fault CodeTo validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop TalkLow voltage on the 5 VDC supply wire can be caused by a short circuit to ground in the supply wire, a short circuit between the supply wire and return circuit, a malfunctioning accelerator, or a malfunctioning ECM power supply.

Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

Possible Cause:1) Accelerator pedal/lever position sensor failure2) OEM harness3) ECM calibration