Diagnostic Routine B

Diagnostic Routine B

Diagnostic Overview

The Anti-Lock Brake System (ABS) Module Does Not Respond To The Scan Tool

Refer to Wiring Diagram Set 14, Module Communications Network for schematic and connector information. Diagrams By Number

Refer to Wiring Diagram Set 42, Vehicle Dynamic Systems for schematic and connector information. Diagrams By Number

Normal Operation and Fault Conditions

The ABS (Anti-Lock Brake System) module communicates with the scan tool through the HS-CAN (High Speed Controller Area Network).

Visual Inspection and Diagnostic Pre-checks

Verify BJB (Battery Junction Box) fuses 43 (40A) and 92 (10A) are OK.

Pinpoint Test

1. CHECK THE ABS (Anti-Lock Brake System) MODULE VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

1. Ignition OFF.

2. Disconnect: ABS (Anti-Lock Brake System) module.

3. Ignition ON.

4. Measure:





Is the voltage greater than 11 volts?






2. CHECK THE ABS (Anti-Lock Brake System) MODULE GROUND CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Disconnect: Negative Battery Cable.

3. Measure:





Is the resistance less than 3 ohms?






3. CHECK THE HS-CAN CIRCUITS BETWEEN THE ABS (Anti-Lock Brake System) MODULE AND THE DLC (Data Link Connector) FOR AN OPEN

1. Measure:





Are the resistances less than 3 ohms?






4. CHECK FOR CORRECT ABS (Anti-Lock Brake System) MODULE OPERATION

1. Ignition OFF.

2. Disconnect and inspect the ABS (Anti-Lock Brake System) module connector.

3. Repair:

- corrosion (replace connector or terminals - clean module pins)

- damaged or bent pins - replace terminals/pins

- pushed-out pins - replace pins as necessary

4. Reconnect the ABS (Anti-Lock Brake System) module connector. Make sure it seats and latches correctly.

5. Operate the system and verify the concern is still present.

Is the concern still present?