Bulb Fail

Bulb failure indication is controlled from two different sources:

If a direction indicator lamp fails, a signal is sent to the instrument pack (pin 18, 48-way connector) from the Body Processor Unit (BPU). The signal is normally low but switched high if a bulb failure occurs; thus causing the bulb fail indicator lamp to illuminate.

If any of the other bulbs, monitored by the three lamp control modules, fail, a signal is sent direct to the instrument pack (pin 43, 48-way connector). The signal is normally low but switched high if a bulb failure occurs; thus causing the bulb failure indicator lamp to illuminate.