Xenon Bulb Monitoring

Xenon Bulb Monitoring
Xenon bulb function is monitored by the Lighting Control Module (LCM E38/E39/E53). The bulbs are only "hot" monitored. Cold monitoring is not possible since the lighting control module is not in direct control of the xenon bulb. For this reason cold monitoring for low beam headlights is encoded off in the lighting control module for Xenon headlight equipped vehicle.

The lighting control module detects xenon bulb failure via a reduction in current flow to the xenon control module. When a bulb fails, the xenon control module's current consumption drops to 60mA indicating unsuccessful xenon bulb illumination. The lighting control module then posts the appropriate matrix display message or LED illumination in the Check Control Pictogram display of the E53 and E39 Low Instrument Clusters.


Xenon Headlight Assembly Components (Example - E53)