P0650

DTC P0650

DTC DESCRIPTOR

DTC P0650
Malfunction Indicator Lamp (MIL) Control Circuit

DIAGNOSTIC FAULT INFORMATION
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Testing and Inspection






CIRCUIT/SYSTEM DESCRIPTION
The malfunction indicator lamp (MIL) is located on the instrument panel cluster (IPC).

The MIL informs the driver that an emission system fault has occurred and that the engine control system requires service. The control module monitors the MIL control circuit for conditions that are incorrect for the commanded states of the MIL.

CONDITIONS FOR RUNNING THE DTC
- The system voltage is 9-18 volts.
- The MIL lamp must be commanded ON for short to battery voltage.
- The MIL lamp must be commanded OFF for an open or short to ground.
- DTC P0650 runs continuously when the ignition is ON.

CONDITIONS FOR SETTING THE DTC
The control module detects that the commanded state of the MIL driver and the actual state of the control circuit do not match for more than 5 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.

CIRCUIT/SYSTEM VERIFICATION
Turn ON the ignition, the MIL should turn ON and OFF when commanded with a scan tool.

CIRCUIT/SYSTEM TESTING
1. With the ignition ON, and the ECM harness disconnected, the MIL should be OFF.
- If the MIL remains ON, test the MIL control circuit for a short to ground. If the circuit test normal, replace the IPC.
2. With the ignition ON, the ECM harness disconnected, connect a fused 3-amp jumper wire to the MIL control circuit. Connecting and disconnecting the other end of the fused jumper wire to a ground will allow the MIL to turn ON and OFF.
- If the MIL turns ON and OFF when the jumper is connected and disconnected from a ground, replace the ECM.
- If the fuse in the 3-amp fused jumper opens, test the MIL control circuit for a short to voltage.
- If the MIL does not illuminate, test the MIL control and the MIL supply voltage circuits for an open. If the circuits test normal, replace the IPC.

REPAIR INSTRUCTIONS
Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Control Module References for control module replacement, setup, and programming.
- Control Module References for IPC replacement, setup, and programming. Verification Tests