For 1990-2009 cars

### 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 00: Malfunction Indicator Lamp (MIL) Control Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
MIL Voltage Supply | P0650 00 | P0650 00 | -- | --
MIL Control | P0650 00/MIL ON | P0650 00 | P0650 00 | --

### 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 states of the MIL.

### Conditions for Running the DTC

• | DTCs P0601 00, P0604 00, P0605 00, P0606 00, P0607 00, and P2610 00 are not set.

• | DTC P0650 00 runs continuously when the ignition is ON.

### Conditions for Setting the DTC

• | The ECM detects that the commanded state of the MIL driver and the actual state of the control circuit do not match for more than 1 s.

• | Should a short circuit to B+ or an open circuit occur on the MIL control circuit, the MIL must be commanded ON for the DTC to set. A short circuit to ground failure on the MIL control circuit can be detected immediately by the ECM in the commanded OFF state.

### Action Taken When the DTC Sets

DTC P0650 00 is a Type B DTC, with no MIL request.

### Conditions for Clearing the DTC

DTC P0650 00 is a Type B DTC, with no MIL request.

### Reference Information

#### Schematic Reference

• | Engine Controls Schematics

• | Instrument Cluster Schematics

#### Connector End View Reference

Component 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

Control Module References for scan tool information

### Circuit/System Verification

1. Ignition ON, the MIL should turn ON and OFF when commanded with a scan tool.
2. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions you observed from the freeze frame/failure records data.

### Circuit/System Testing

1. Ignition ON, verify that the P16 Instrument Panel Cluster (IPC) warning indicators are illuminated.

⇒ | If the P16 Instrument Panel Cluster (IPC) indicators are not illuminated, test the ignition circuit terminal 32 (X1) for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, replace the P16 Instrument Panel Cluster (IPC).

2. Ignition OFF, disconnect connector X2 at the K20 Engine Control Module (ECM).
3. Ignition ON, verify that the MIL is not illuminated.

⇒ | If the MIL is illuminated, inspect the MIL control circuit terminal 68 (X2) for a short to ground. If the circuit tests normal, replace the P16 Instrument Panel Cluster (IPC).

4. Ignition ON, verify that the MIL illuminates with a 3 A fused jumper between the K20 Engine Control Module (ECM) MIL control circuit terminal 68 (X1) and ground

⇒ | If the MIL does not illuminate, test the MIL control circuit terminal 68 (X2) for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module (ECM).

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Instrument Cluster Replacement

• | Control Module References for ECM replacement, setup, and programming