ABS Warning Light
If a fault occurs in any of the ABS control module's inputs/outputs or if the supply of current (+15 circuit) fails, the control module will earth pin 21, which causes the ABS warning lamp in the main instrument unit to come on. Diagnosis of constituent components are carried out continuously and starts when the ignition switch is turned to the Drive position. If all the circuits are OK the ABS lamp goes out after 3-5 seconds. If a fault arises while the car is being driven, the ABS lamp, the brake fluid warning lamp and the central warning lamp will come on. The ABS is disabled at the same time.
Diagnosis
The 26-pin connector has a short-circuit contact strip which closes when the connector is unplugged from the control unit. This causes the ABS lamp, the brake fluid warning lamp and the central warning lamp to come on.