Circuit DescriptionThe sensor supply 5 of the electronic control module (ECM) provides a 5 volt supply for the aftertreatment diesel particulate filter differential pressure sensor, remote accelerator, engine coolant level sensor, fan speed sensor, and the accelerator position sensor 2.

Component LocationSensor supply number 5 is located in the ECM OEM harness connector and provides a 5 volt supply to various components in the OEM harness.

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 ECM detects that the sensor supply 5 signal voltage is less than 4.75-VDC for more than 1 second.

Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE light and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.The engine will have limp home throttle control only.Conditions for Clearing the Fault CodeTo validate the repair, 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 after the diagnostic runs and passes.For OBD engines, the ECM will turn off the MIL after 3 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 volt supply wire can be caused by a short circuit to ground in a supply wire, a short circuit between a supply wire and a return wire, a damaged sensor, or a damaged ECM power supply.

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

For intermittent power supply and datalink communication issues with Aftertreatment Components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing or intermittent connections.

Possible Cause:1) Accelerator/lever position sensor failure2) Aftertreatment Diesel Particulate Filter differential pressure sensor failure3) Engine Coolant level Sensor failure4) Remote accelerator pedal/lever failure5) Fan speed sensor failure6) OEM harness7) ECM calibration