Component Tests and General Diagnostics

The brake system uses two warning indicators to alert the driver of malfunctions in the system.

The red brake warning indicator will come on for only two reasons:

1. If the brake fluid level in the brake master cylinder reservoir falls below the level which is determined by the switch point of the fluid level switch.
2. If the parking brake is applied.

The amber anti-lock brake warning indicator will come on to indicate numerous concerns:
^ It warns the driver that the anti-lock brake system has been turned off due to a condition that exists in the system.
^ Normal power-assisted braking remains while the amber anti-lock brake indicator is on but the wheels can lock during a panic stop.
^ The anti-lock brake control module monitors system operation and can store all defined Diagnostic Trouble Codes (DTCs) in its keep-alive random access memory.
^ Certain procedures must be followed to find the fault in this situation.

WARNING: FOLLOWING THE WRONG SEQUENCE OR BYPASSING DIAGNOSTIC STEPS WILL LEAD TO UNNECESSARY REPLACEMENT OF PARTS AND/OR INCORRECT RESOLUTION OF THE SYMPTOM.

Follow the diagnostic procedures step-by-step in order as indicated within the diagnostic tests.
^ The anti-lock brake control module cannot recognize some failures; therefore if a concern exists and no DTCs are stored by the anti-lock brake control module, other diagnostic steps must be followed.
^ The anti-lock brake control module cannot store a DTC if it is not supplied battery positive voltage (B+).
^ This condition can be found by using the Quick Test Check Sheet.

The following equipment is recommended for diagnosing anti-lock brake system:
^ Anti-Lock Breakout Box Adapter 418-FO41 (007-00116) or equivalent.
^ EEC-IV 60-Pin Breakout Box 418-005 (014-00322) or equivalent.
^ New Generation Star (NGS) Tester 418-FO48 (007-00500) or equivalent.
^ 73 Digital Multimeter 105-R0051 or equivalent.