GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2007 🢒 LaCrosse 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0650

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 provides an overview of each diagnostic category.

DTC Descriptor

DTC P0650: Malfunction Indicator Lamp (MIL) Control Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open

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 powertrain control module (PCM) monitors the MIL control circuit for conditions that are incorrect for the commanded states of the MIL.

Conditions for Running the DTC

DTC P0650 runs continuously when the ignition is ON.

Conditions for Setting the DTC

The PCM detects that the commanded state of the MIL driver and the actual state of the control circuit do not match for more than 1 second.

Action Taken When the DTC Sets

DTC P0650 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0650 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Powertrain Control Module Connector End Views
    •  Engine Controls Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Circuit/System Verification

Turn ON the ignition, then command the MIL ON and OFF with a scan tool. The MIL should turn ON and OFF when commanded.

Circuit/System Testing
  1. Turn OFF the ignition.
  2. Disconnect the PCM.
  3. Turn ON the ignition with the engine OFF.
    4. ⇒If the MIL is still ON, test the MIL control circuit for a short to ground.
    ⇒If the MIL control circuit tested OK and the MIL stayed ON, replace the instrument cluster. Refer to Instrument Cluster Replacement .
    ⇒If the MIL control circuit tested OK and the MIL went out when the PCM was disconnected, replace the PCM. Refer to Control Module References .
  4. Measure for 12 volts from the MIL ignition voltage circuit in the instrument cluster harness connector to a ground.
    5. ⇒If there is less than 12 volts, test the MIL ignition voltage circuit for an open, or a short to ground, and an open fuse.
  5. Remove the fuse that supplies voltage to the MIL.
  6. Measure for less than 1 volt from the MIL control circuit in the PCM harness connector to a good ground.
    7. ⇒If there is more than 1 volt, test the MIL control circuit for a short to voltage.
  7. Install the fuse that supplies voltage to the MIL.
  8. The MIL should illuminate with a 3-amp fused jumper wire connected between the MIL control circuit in the PCM harness connector and a good ground.
    9. ⇒If the MIL does not illuminate, test the MIL control circuit for an open or high resistance.
    ⇒If the MIL control circuit tests OK, replace the instrument cluster. Refer to Instrument Cluster Replacement .
    ⇒If the MIL does illuminate, but does not when commanded ON with a scan tool, replace the PCM. Refer to Control Module References .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for PCM replacement, setup, and programming