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.

### Circuit Description

The instrument panel cluster (IPC) illuminates the stabilitrak indicator during the IPC bulb check or when the electronic brake control module (EBCM) sends a serial data message to the IPC commanding the indicator ON.

### Reference Information

#### Schematic Reference

Antilock Brake System Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

ABS Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information.

### Circuit Verification

Ignition On, with a scan tool command the IPC display test ON and OFF. The stabilitrak indicator should turn ON and OFF.

⇒ | If the Stabilitrak indicator does not turn ON and OFF, replace the IPC.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the traction control switch.
2. Test for less than 5 ohms between the ground circuit terminal H and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify the scan tool BCM TCS Switch State parameter is Released.

⇒ | If not the specified value, test the signal circuit terminal J for a short to ground. If the circuit tests normal, replace the BCM.

4. Install a 3A fused jumper wire between the signal circuit terminal J and the ground circuit terminal H. Verify the scan tool BCM TCS Switch State parameter is Pressed.

⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

5. Ignition ON, verify the scan tool BCM Traction Switch LED parameter is OFF.

⇒ | If not the specified value, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the BCM.

6. Install a 3A fused jumper wire between the signal circuit terminal B and the ground circuit terminal H. Verify the scan tool BCM Traction Switch LED parameter is ON.

⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

7. If all circuits test normal, test or replace the traction control switch.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Accessory Switch Replacement

• | Control Module References for BCM replacement, setup, and programming.