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
--- | --- | --- | --- | ---
Traction Control Switch Signal | B2745 02 | 1 | 1 | --
Traction Control Switch Ground | -- | 1 | -- | --
1. Traction Control Switch Inoperative

### Circuit/System Description

The instrument cluster illuminates the traction control/stability control-active indicator, traction control off indicator and stability control off indicator for 5 s after ignition ON. The electronic brake control module (EBCM) will request the instrument cluster via serial data to turn the traction control/stability control-active indicator ON (flashing) when the system is in traction control or stability control mode. When the EBCM detects a fault it sends a serial data message to the instrument cluster commanding the traction control/stability control-active indicator ON.

The body control module (BCM) monitors the traction control switch. When the traction control switch is pressed once, the BCM will request the EBCM via serial data to disable the traction control. When the traction control switch is pressed for 5 s, the BCM will request the EBCM to disable the stability control. The EBCM will request the instrument cluster via serial data to turn the traction control off and stability control off indicator ON to notify the driver of the deactivation.

### 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 instrument cluster All Indicators test ON and OFF. Verify the traction control/stability control-active indicator, traction control off indicator and stability control off indicator turn ON and OFF.

⇒ | If either indicator does not turn ON and OFF, replace the P16 Instrument Panel Cluster (IPC).

2. Observe the scan tool EBCM Traction Control Switch parameter while pressing and releasing the traction control switch. Verify the reading changes between Active and Inactive.

⇒ | If the parameter does not change between the specified values, refer to Circuit/System Testing.

3. Observe the scan tool EBCM Vehicle Stability Enhancement System Switch parameter while pressing the traction control switch for 5 s and releasing. Verify the reading changes between Active and Inactive.

⇒ | If the parameter does not change between the specified values, replace the K9 Body Control Module (BCM).

4. Observe the traction control off indicator while pressing and releasing the traction control switch. Verify the traction control off indicator turns ON and OFF.

⇒ | If the traction control off indicator does not turn ON and OFF, replace the K17 Electronic Brake Control Module (EBCM)

5. Observe the stability control off indicator while pressing the traction control switch for 5 s and releasing. Verify the stability control off indicator turns ON and OFF.

⇒ | If the stability control off indicator does not turn ON and OFF, replace the K17 Electronic Brake Control Module (EBCM)

### Circuit/System Testing

Note: Circuit/System Verification must be performed before Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the S48C Multifunction Switch - I/P.
2. Test for less than 5 Ω between the ground circuit terminal 2 and ground.

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

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

⇒ | If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the K9 Body Control Module (BCM).

4. Install a 3 A fused jumper wire between the signal circuit terminal 7 and ground for 2 s.
5. Verify the scan tool EBCM 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. If the circuit tests normal, replace the K9 Body Control Module (BCM).

6. If all circuits test normal, test or replace the S48C Multifunction Switch - I/P.

### Component Testing

#### Static Test

1. Ignition OFF, disconnect the harness connector at the S48C Multifunction Switch - I/P.
2. Test for infinite resistance between the signal circuit terminal 7 and the ground circuit terminal 2 with the switch in the released position.

⇒ | If less than the specified value, replace the S48C Multifunction Switch - I/P.

3. Test for less than 5 Ω between the signal circuit terminal 7 and the ground circuit terminal 2 with the switch in the pressed position.

⇒ | If greater than the specified value, replace the S48C Multifunction Switch - I/P.

### Repair Instructions

• | Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | LINK 183965

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