Test requirements
- Permissible and identical wheels and tire size Correct tire pressure at all wheels.
- Mechanical and hydraulic parts of the brake system must be in order: Hydraulic connections and lines are not leaking (visual check of hydraulic unit, brake callipers, wheel brake cylinder, tandem brake master cylinder).
- Wheel bearings and wheel bearing play OK.
See SUSPENSION - FRONT .
See SUSPENSION - REAR .
- Wheel speed sensors must be installed correctly.
See ANTILOCK BRAKE SYSTEM .
- Supply voltage OK (min. 10.5 V).
- Ground (GND) connection for return pump -V39- on hydraulic unit must be OK.
- Connector properly attached to ABS Control Module (w/EDL) -J104-, catch engaged.
- The diagnosis procedure can only be started with the vehicle stationary and the ignition switched on (or with engine running). The diagnosis cannot be started if wheel speed exceeds 1.65 mph (2.75 km/h). Diagnosis is terminated if speed exceeds 12.4 mph (20 km/h).
- While testing the ABS, ABS/EDL and ASR systems, ensure that the vehicle's electrical devices are not subjected to electromagnetic interference: keep the vehicle away from equipment with a high current draw such as electric welding units.