Golf Mk3
|
Self-diagnosis function ITT Mark 20 GI
Function
The ABS designation has been changed: Previously: Teves 20 GI New: ITT Mark 20 GI The work sequence and function has not changed because of the new designation. Both ABS systems are identical. The self-diagnosis relates to the electrical/electronic part of the ABS, in other words only faults via the electrical connection to the control unit are recognised (e.g. speed sensor open circuit). The 25 pin ABS control unit (J104) forms with the hydraulic unit a compact unit. The unit is located on the left of the engine compartment. The control unit is equipped with a fault memory. The diagnostic connections are located behind the cover next to the ashtray. The control unit recognises faults and malfunctions during vehicle operation and stores them in a permanent memory, the contents of which remain despite the lack of battery voltage. Sporadic (isolated) faults will also be recognised and stored. But if these faults do not occur again within the next 50 vehicle starts and driving off sequences then with the exception of "control unit defective", the fault memory will be erased. After switching on the ignition and/or starting the engine the ABS warning lamp (K47) and the brake system red warning lamp (K118) lights up for approx. 2 seconds. During this period a test sequence (self-check) is run in the control unit for the following functions:
The self diagnosis must be initiated at the commencement of fault finding and the stored information interrogated with the Fault reader V.A.G 1551 The fault information displayed is used in conjunction with a fault table which has information on the possible fault causes for pin-pointed repair measures. With the ITT Mark 20 GI system the self-diagnosis has been complemented by the functions Read measured value block, Code control unit, Basic setting (is only required for vehicles with EDL) and Final control diagnosis. |
