Diagnosis & Testing: Notes

NOTE: For more information, see ANTI-LOCK BRAKE SYSTEM - ABS-VI article in the BRAKES section.

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.

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 for Diagnostic Trouble Codes (DTC). Attach Tech 1 scan tester to Data Link Connector (DLC), and follow Tech 1 scan tester instructions to retrieve DTCs. If DTCs are found, proceed to diagnostic flow charts. See DIAGNOSTIC CHARTS .

If no DTC 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 .