Headlight issues!

Hi Guys, my 03 P5 recently had its fumper, headlight and fender replaced, since then I noticed my headlights do not activate when I turn them on. Furthermore, when I switch to highs, nothing happens. The strangest part is the dash illuminates when the headlights are turned on but the Hig beam indicator will not. I have working markers/signal/running lights/hazards, checked fuses connections and the relay(7), still nohing. As a side note, the only cable I can find under the hood that is not connected to anything is thin and black, coming out of a small diagnosis box near the windshield. I realise I dont have too much info here, and over-the-web diagnosis can be tricky but any sort of suggestions would be great since I do a fair amount of night driving. THX in advance!!(canada)

Djony Montana said:

Hi Guys, my 03 P5 recently had its fumper, headlight and fender replaced, since then I noticed my headlights do not activate when I turn them on.

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Take it back to whoever did the work and have them fix this. They should be embarrassed to have delivered a car to a customer in that condition.

If you did the work then pull the cable off one of the low beam lights, put a voltmeter's probes into the two slots, and check the voltage with the headlights "on". If none, find the headlight fuse and check it for continuity. (Pull it, set the multimeter to its continuity setting, if it has one, or to a low resistance setting. The fuse should measure about the same as shorting the multimeter probes.) If the fuse is OK, go back to the cable and work your way back down it until you find the place where the expected voltage appears. I have never worked on that circuit, farther back than the bulb, but I would guess that the stalk switch sends low current voltages to relays, which actually switch the current for the bulbs. There is a shop manual linked from a sticky at the top of this forum, you can find the diagrams there.

...and inspect for a unconnected ground wire.

So my mechanic seems to think it's a switch issue because bridging a connection in the relays port causes them to function properly. Now I have a piece of wire in lieu of a relay.