Fault-finding

FAULT-FINDING

AUTOMATIC CHECK UPON IGNITION: when the car is started the "ABS warning light" on the instrument cluster turns on for appr. 2 secs., then it goes off meaning that the system is working properly. If the warning light stays on, carry out diagnosis using the flashing code, as mentioned follows.

If the warning light does not turn on, carry out test H.

N.B.: When the control unit detects an error in the "ABS" function and turns on the warning light , it simultaneously deactivates the system, therefore, in these conditions the car brakes only with the conventional system. When the control unit also detects an error of the "EBD" function, it turns on both warning lights [symbol] e [symbol]. Under these conditions also control of the rear braking distribution is deactivated, and the car must be driven very carefully.

Fault-Finding using the Flashing Code

The self-diagnosis system with which this system is fitted, makes it possible to quickly locate a faulty component following the instructions of a FLASHING CODE, which is activated as follows:

• earth the line of pin 1 of connector T8 (LIGHT BLUE-WHITE cable)
• power the ABS control unit N51 (turning the ignition key to MARCIA)

Read the sequence of flashes on the "ABS warning light" on the instrument cluster C10:

• after appr. 3 seconds for three times code "12" appears, meaning correct operation: if this does not occur, carry out test H
• after another 3 seconds appr. the codes of the errors memorised appear (each repeated three times) at appr. 3 sec. intervals (see table on following page)

• at the end, code "12" appears for another three times, indicating the end of the sequence
• of disconnecting pin 1 of T8, after 2 seconds the system resumes normal operation.

NOTE: Resetting the memorised code is obtained by of disconnecting the line of pin 1 of T8 and engaging the ignition switch 20 times (or using the ALFA ROMEO Tester)

Fault-finding using the Alfa Romeo Tester

N.B. Before carrying out diagnosis with the Tester, perform the preliminary check described later (TEST A); if the warning light is not working properly also carry out TEST H.

The connection between the TESTER and the control unit must be made as follows:

1. Supply the TESTER either through the cigar lighter socket or connecting directly to the battery using the special lead.
2. Connect the TESTER socket to the control unit (the socket is near the control unit).

The instrument can give the following information:

• parameter display;
• error display;
• active diagnosis.

Activation of diagnosis

Diagnostic conversation is started with the engine stopped and the ignition key at MARCIA.