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Fault diagnosis, ABS warning lamp (MIU 2)

Fault diagnosis, ABS warning lamp (MIU 2)

Fault symptom

The lamp does not light up when the ignition switch is turned to the Drive position.

Diagnostic procedure



1. If the lamp does not light up the bulb is probably faulty and will have to be changed.

If the lamp still does not light up after changing the bulb, continue with point 2.

2. Connect a BOB to the main instrument display panel's 56-pin connector.

3. Check the operation of the main instrument display panel and the lamp by grounding pin 16 on the BOB with the ignition switched on.

First make sure that the central warning lamp is not alight. The ABS warning lamp and the central warning lamp should light up. If only the central warning lamp lights up, then the ABS warning lamp is faulty. Continue with point 4.

If both lamps light up, there is an open circuit in the wiring connected to the ABS control module. Continue with point 5.

If none of the lamps light up, the fault is probably in the main instrument display panel's processor card. Continue on page

4. Change the bulb.

If the lamp still fails to light up when activated, check that the new bulb is OK by fitting it in place of another bulb in the main instrument display panel that does light up.

If the lamp still does not light up, there could be an internal fault in the main instrument display panel. Remove the main instrument display panel's rear section complete with processor card and check that all leads connected to the connector marked CN4 are securely located.

If any lead has worked loose or is broken, continue on .

If the connections in the connector are OK, the fault is probably in the intermediate part with bulbs and indicating instruments. Continue on .

5. Check that the wiring between the main instrument display panel and the ABS control module is OK by connecting a BOB to the 25-pin ABS control module connector (the main instrument display panel and ABS control module should not be connected).



6. Check for an open circuit by taking a reading across pin 16 on the BOB connected to the main instrument display panel and pin 1 on the BOB connected to the ABS control module.

7. If the wiring is OK, continue fault diagnosis as described in Service Manual 5 "Brakes".