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/System Description

Battery voltage is supplied to the antilock brake system (ABS) warning lamp with the ignition switch in the ON or START positions. The warning lamp can be activated only by the ABS control module internally supplying ground to terminal 10 or by the shorting bar in the ABS module connector when it is disconnected from the module.

### 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 Testing

1. Ignition OFF, disconnect the EBCM connector.
2. Ignition ON, check to see that ABS warning indicator is illuminated.

⇒ | If the ABS warning indicator is illuminated, replace the BPMV/EBCM

3. Ignition OFF, disconnect the IP connector.
4. Ignition ON, check for B+ between terminal A5 and ground.

⇒ | If the voltage is not as specified, test the B+ circuit for a short to ground or an open/high resistance.

5. Test for less than 1 ohm between the terminal 10 of the EBCM connector and terminal A2 of the IP connector.

⇒ | If greater than the specified range, test the circuit for an open/high resistance. If the circuit tests normal, replace the BPMV/EBCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM replacement, setup, and programming