FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Filament Monitor, Front Lights



Filament Monitor, Front Lights










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

The SID unit sends B+ to the filament monitor via pin 10. If a headlamp bulb is faulty, the filament monitor output will be grounded.

The SID unit uses the information for a CHECK message (3 second 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.