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
--- | --- | --- | --- | ---
Signal | -- | 1 | B2745 | --
Ground | -- | 1 | -- | --
1. Traction Control Indicator Malfunction

### Circuit/System Description

The traction control system (TCS) switch is a normally open switch that closes when the switch is activated. When activated, the switch grounds the TCS signal circuit. The body control module (BCM) converts the signal into serial data, which is used by the electronic brake control module (EBCM) to enable/disable the TCS.

### 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/System Verification

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

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

2. Observe the scan tool BCM Traction Control Switch parameter while pressing and releasing the traction control switch. The reading should change between Active and Inactive.

### Circuit/System Testing

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

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

3. Ignition ON, verify the scan tool Traction Control Switch parameter is Inactive.

⇒ | If not the specified value, test the signal circuit terminal 8 for a short to ground.

4. Install a 3A fused jumper wire between the signal circuit terminal 8 and the ground circuit terminal 2. Verify the scan tool Traction Control Switch parameter is Active.

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

5. If all circuits test normal, test or replace the traction control switch. If the DTC resets, replace the BCM.

### Component Testing

1. Ignition OFF, disconnect the harness connector at the traction control switch.
2. Test for infinite resistance between the signal terminal 8 and the ground terminal 2 with the switch in the open position.

⇒ | If not the specified value, replace the traction control switch.

3. Test for less than 3 ohms between the signal terminal 8 and the ground terminal 2 with the switch in the closed position.

⇒ | If greater than the specified range, replace the traction control switch.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming