Anti-Lock Brake System: Diagnosis: Notes

NOTE: To diagnose ABS/TCS system, manufacturer recommends using Tech 1 Scan Tester (94-00101-A) with 1988-95 Brake Cartridge. Some diagnostic procedures will require EBCM/EBTCM Pinout Box (J-39700) with Adapter Cable (J-39700-25) and High-Impedance Digital Multimeter (J-39200) or equivalent. When using Tech 1 for diagnostics, ABS system is disabled by EBCM. ANTI-LOCK indicator will come on indicating only normal power assisted braking is available. After diagnostics have been completed using Tech 1, disconnect Tech 1 from Data Link Connector (DLC) and turn ignition off for at least 10 seconds before road testing. This procedure is done to reset EBCM.

The EBCM/EBTCM has self-diagnostic capability, which can detect system failures. Fault codes stored by EBCM/EBTCM can be displayed using Tech 1 scan tester. There are no provisions for flash code diagnostics.

Begin ABS/TCS diagnosis with PRE-DIAGNOSTIC INSPECTION procedure. If failures are found during pre-diagnostic inspection, perform necessary repairs, and proceed with ABS/TCS FUNCTIONAL CHECK. See Figure .

If no failures are found during pre-diagnostic inspection, go to ABS/TCS FUNCTIONAL CHECK. See Figure . The ABS/TCS FUNCTIONAL CHECK will either indicate ABS/TCS is functioning properly or direct technician to various diagnostic procedures such as diagnostic charts, symptom diagnosis or BRAKE warning light diagnosis.