AD42.30-D-3020A | Anti-lock brake system (ABS/ABD) inspection | 10.6.97 |
MODELS 901.0##, 902.0##, 903.0##, 904.0##, 901.3##, 902.3##, 903.3##, 904.3##, 901.4##, 902.4##, 903.4##, 904.4## ## up to 718186 up to 30.6.97 with CODE (BB0) Brake system anti-lock brake system ABS
Anti-lock brake system ABS/ABD Diagnosis, previous knowledge | |||
| Using the HHT, perform the following tests on the roller test bench or with the wheels raised. After switching on the ignition, the Sila ABS and information display ABD must extinguish after approx. 2 seconds | ||
| If a dynamic speed sensor error (104, 105, 112, 113) occurred during the last trip which has now been rectified or if the control module was replaced, the Sila ABS only extinguishes once the vehicle speed exceeds 12 km/h. Only then is the internal speed sensor test performed. | ||
Test step | Inspecting | Note | |
1 | Assignment of speed sensors | Drive all wheels individually in succession. The wheel speed for the wheel currently driven must be determined | |
2 | Air gap | Slowly accelerate all wheels individually, all wheels of one axle or all wheels together. From a certain wheel speed, a speed value must be determined for each wheel driven. | |
3 | Assignment of wheel brakes | Press the brake pedal until it becomes difficult to turn the wheel (roller test bench brake power 1 kN). Switch on the intake valve of the particular wheel and increase the brake power. It must still be difficult to turn the wheel (roller test bench brake power constant). Switch on the exhaust valve. It must be possible to easily rotate the wheel. Switch off the intake valve and check the next wheel in the same way | |
4 | Road test | If errors did not occur during the test, leave the diagnosis mode and accelerate the vehicle to over 12 km/h. The Sila ABS must extinguish and remain switched off at this speed at the latest. Then drive the vehicle faster then 50 km/h for at least 80 seconds. Only then are the internal monitoring procedures for the system complete. |