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Filament monitor, front lights

Filament monitor, front lights




General

The SID receives information from the filament monitor concerning the functionality of the headlamps.

The SID supplies B+ to the filament monitor via pin 25. If a headlamp bulb is faulty, the filament monitor output will be grounded.

The SID uses the information to generate a CHECK message (3 seconds delay).

Diagnosis

If a short-circuit to ground occurs in the filament monitor circuit, the CHECK message for a faulty lamp will be shown even though the lamp is OK.

In the event of an open circuit, the CHECK message will not be shown even if one of the lamps is faulty.