Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provide an overview of each diagnostic category. |
DTC Descriptor
DTC P0650: Malfunction Indicator Lamp (MIL) Control CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
MIL Voltage Supply | P0650 | P0650 | -- | -- |
MIL Control | P0650/MIL ON | P0650 | P0650 | -- |
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 engine control module (ECM) monitors the MIL control circuit for conditions that are incorrect for the commanded state of the MIL. For example, a failure condition exists if the ECM detects low voltage when the MIL is commanded OFF, or high voltage when the MIL is commanded ON.
Conditions for Running the DTC
| • | The engine speed is more than 80 RPM. |
| • | The ignition voltage is between 10-18 volts. |
| • | The ECM has commanded the MIL ON and OFF at least once during the ignition cycle. |
| • | DTC P0650 runs continuously once the above conditions are met . |
Conditions for Setting the DTC
| • | The ECM detects an open, a short to ground, or a short to voltage on the circuit that controls the MIL. |
| • | The condition exists for at least 4 seconds. |
Action Taken When the DTC Sets
DTC P0650 is a Type B DTC.
Conditions for Clearing the DTC
DTC P0650 is a Type B DTC.
Diagnostic Aids
If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the circuit status for the component with a scan tool. The circuit status parameter changes from OK or Indeterminate to Fault if there is a condition with the circuit or a connection.
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
Ignition ON, command the MIL ON and OFF with a scan tool. The MIL should turn ON and OFF as commanded.
Circuit/System Testing
- If any other IPC indicators or gages are inoperative, refer to Instrument Cluster Gages Inoperative .
- Ignition OFF, disconnect the ECM harness connectors. Ignition ON, the MIL should not illuminate.
- Ignition ON, connect a 3A fused jumper wire between the MIL control circuit and ground. The MIL should illuminate.
- If all circuits/connections test normal, replace the ECM.
| ⇒ | If the MIL is illuminated, test the MIL control circuit for a short to ground. If the circuit tests normal, replace the IPC. |
| ⇒ | If the MIL does not illuminate, test the MIL control circuit for a short to voltage, or an open/high resistance. If the circuit test normal, replace the IPC/bulb. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for engine control module replacement, setup, and programming |
