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Fault diagnosis, instrument lighting (MIU1)

Fault diagnosis, instrument lighting (MIU 1)

Fault symptoms

The instrument background lighting is inoperative when the rheostat is activated but the other instrument lighting is OK.

Diagnostic procedure



1. Unplug the main instrument display panel's 3 connectors and connect the Scan Tool's test leads to pin 12 (12p-2) and ground. Then select "TEST" followed by "PULSE".

If in proper working order, the reading obtained should be between 53 and 93 Hz.

The ignition should be switched on.

2. If the reading obtained is not OK, check the wiring for continuity/shorting by measuring the resistance across pin 2 (12p-2) of the main instrument display panel and pin 2 of the rheostat.



The resistance reading obtained should be < 1 ohm.