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Filament monitor, front lights

Filament monitor, front lights





General

The SID unit receives information on headlamp functionality from the filament monitor.

The SID unit sends B+ to the filament monitor via pin 23. If a headlamp bulb is faulty, the filament monitor output will be grounded.

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

Diagnostics

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.