Anti-Lock Brake System: Introduction: Notes

The procedures contained in this article include all the specifications, instructions, and graphics needed to diagnose Mark 20 Anti-Lock Braking System (ABS) problems. The diagnostics in this article are based on the failure condition or symptom being present at time of diagnosis.

Follow the recommendations below when choosing your diagnostic path.

1. First make sure the DRBIII(R) is communicating with the Controller Anti-Lock Brake (CAB). If the DRBIII(R) displays a "No Response" condition, you must diagnose that first.
2. Read DTC's (diagnostic trouble codes) with the DRBIII(R).
3. If no DTC's are present, identify the customer complaint.
4. Once the DTC or customer complaint is identified, locate the matching test in DIAGNOSTIC INFORMATION AND PROCEDURES  and begin to diagnose the symptom.

All component location views are in COMPONENT LOCATIONS  . All connector pinouts are in CONNECTOR PINOUTS  . All schematics are in SCHEMATIC DIAGRAMS  .

An asterisk (*) placed before the symptom description indicated a customer complaint.

When repairs are required, refer to the appropriate service information for the proper removal and repair procedure.

Diagnostic procedures change every year. New diagnostic systems may be added; carry over systems may be enhanced. READ THIS INFORMATION BEFORE TRYING TO DIAGNOSE A VEHICLE CODE. It is recommended that you review the entire service information to become familiar with all new and changed diagnostic procedures.