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.

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition | 1 | 1 | -- | --
Shift Lock Solenoid Control | -- | 1 | 2 | --
1. Shift lever will move from PARK without pressing the brake pedal 2. Shift lever will not move from PARK with the brake pedal pressed

### Circuit/System Description

The ignition lock module controls the shift lock solenoid through a low side drive control circuit. When the ignition is on and the shift lever is in the park position, the ignition lock module will energize the shift lock solenoid by grounding the control circuit. The stop lamp switch signal provides an input to the ignition lock module and when the brake pedal is pressed, the ignition lock module will de-energize the shift lock solenoid.

### Reference Information

#### Schematic Reference

Shift Lock Control Schematics

#### Connector End View Reference

Shift Lock Control Connector End Views

#### Description and Operation

Automatic Transmission Shift Lock Control Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### Circuit/System Verification

1. Ignition ON, the shift lever should be locked in the park position.
2. With the brake pedal pressed the shift lever can be moved out of the park position.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the automatic transmission shift lever.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 4 and ground.

⇒ | If the test lamp does not illuminate, test the ignition circuit for an open/high resistance or short to ground.

3. Connect a test lamp between B+ and the control circuit terminal 3.
4. Ignition ON, press and release the brake pedal. The test lamp should turn ON and OFF when changing between the commanded states.

⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the ignition lock module.

⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ignition lock module.

5. If all circuits test normal, test or replace the shift lock control solenoid.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Shift Lock Control Solenoid Replacement