Test Driving ABS Complaint Vehicles

Most ABS complaints will require a test drive as a part of the
diagnostic procedure. The purpose of the test drive is to duplicate the condition.

Before test driving a brake complaint vehicle, especially if the BRAKE warning lamp is on, test the brakes at low speed to be sure that the car will stop normally. Remember that conditions that result in illumination of the BRAKE warning lamp may indicate reduced braking ability. The following procedure should be used to test drive an ABS complaint:

1) Ignition on. Turn the ignition to the ON position without starting the car and wait until the BRAKE warning and ANTI-LOCK warning lamps turn off. This will allow the pump to charge the accumulator to operating pressure. If the warning lamp(s) do not turn off, proceed to step 3.

(2) Ignition off for 15 seconds.

(3) Start car. Wait for displays to return to normal operating mode before proceeding.

(4) With Shift lever in PARK, slowly depress brake pedal and release.

(5) Drive vehicle a short distance. During this test drive, be sure that the vehicle achieves at least 20 mph. Brake to at least one complete stop and accelerate slowly to at least 20 mph.

(6) If a functional problem with the ABS system is determined while test driving a vehicle refer to the BENDIX ANTI-LOCK 10 DIAGNOSTICS MANUAL for required test procedures and proper use of the DRB II tester.

The following are general precautions which should be observed when servicing and
diagnosing the ABS system and/or other vehicle systems. Failure to observe these precautions may result in ABS system damage.

(1) If welding work is to be performed on the vehicle using an arc welder, the (CAB) should be disconnected before the welding operation begins.

(2) The CAB) and hydraulic assembly 10 way connectors should never be connected or disconnected with the ignition on.

(3) Some components of the ABS system are not serviced separately and must be serviced as complete assemblies. Do not disassemble any component which is designated as non-serviceable.

(4) Always de-pressurize the Hydraulic Accumulator when performing any work which requires disconnecting any hydraulic tube, hose or fitting. The ABS system uses brake fluid at high pressure. Failure to de-pressurize the accumulator may result in personal injury and/or damage to painted surfaces.

Brake fluid will damage painted surfaces. If brake fluid is spilled on any painted surf aces, wash off with water immediately.