Anti-Lock Brake System: Diagnosis: Notes

NOTE: Tech 1 scan tester, most current Mass Storage Cartridge (MSC) and High-Impedance Multimeter (J-39200) or equivalent are required to test parts of ABS system.

Before attempting any diagnostic procedures, road test vehicle to verify complaint. Perform pre-diagnostic visual inspection to detect obvious problems. See PRE-DIAGNOSTIC INSPECTION . Repair problems if necessary, and retest vehicle.

If no obvious problem is found, scan ABS system for Diagnostic Trouble Codes (DTC). Attach Tech 1 scan tester to Data Link Connector (DLC), and follow Tech 1 scan tester instructions to retrieve codes. See USING TECH 1 . If codes are found, proceed to diagnostic flow charts. See DIAGNOSTIC CHARTS .

If no code is displayed, test drive vehicle while using Automatic Snapshot feature of Tech 1 scan tester. See USING TECH 1. If failures cannot be reproduced, use Enhanced Diagnostic feature to reveal ABS fault history. See ENHANCED DIAGNOSTICS .