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Fault diagnosis, instrument lighting (MIU 2)

Fault diagnosis, instrument lighting (MIU 2)

Fault symptom

Instrument lighting for the tachometer, tank/temp/turbo gauges and speedometer does not come on, nor do the central warning and INFO DISPL lamps light up.

Diagnostic procedure



1. Connect an ISAT Scan Tool and select "TEST FUNCTIONS" followed by "INSTR LIGHTG TEST".

If in proper working order, the following will take place:

The Scan Tool sets the light intensity (from the light sensor) at 0 and increases it (from the rheostat) from 0 to maximum for 10 seconds.

The instrument lighting will now increase from 0 to maximum brightness.

Following this, the Scan Tool increases the light intensity (from the light sensor) from 0 to maximum.

After 2-3 seconds a threshold point is reached (corresponding to daylight) at which the instrument lighting goes out and the brightness of the indicator lamps increases.

2. If any lamp does not light up, its bulb is probably faulty and must be changed.

If the replacement 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 bulb is OK but the lamp does not light up during the lamp self-test, the fault is in the processor card. Continue on .