Headlight/electrical problem!
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Headlight/electrical problem! So every once in a while I'm driving along, and my headlights stop illuminating and at the same time I hear a crackling sound coming from under the dash, exactly like a short. The sound stops eventually and a couple seconds after, the headlights will illuminate again. All other lighting/electrical systems work fine (even the fogs) the during the entire sequence. 99% of the time the headlights work fine, so I can't really figure out where the noise is coming from (as I'm driving at the time). Thankfully I have really f*cking bright fog lights that work, so I'm not completely blind when the headlights go out.
How can I fix this?
Some potentially useful/useless background info: for a long time my side-post Optima had damaged threads on the female connector and would make for a loose negative cable and bad grounding, causing all the electrical in the vehicle to dim every once in a while, the voltage gauge to jump back and forth, and the ABS INOP light to come on. Recently changed it to top-post and thats about when the headlight thing started happening.
How can I fix this?
Some potentially useful/useless background info: for a long time my side-post Optima had damaged threads on the female connector and would make for a loose negative cable and bad grounding, causing all the electrical in the vehicle to dim every once in a while, the voltage gauge to jump back and forth, and the ABS INOP light to come on. Recently changed it to top-post and thats about when the headlight thing started happening.
Do you use the auto headlights? If you turn the switch on does it go away?
The auto headlights uses a relay, in the BCM, and if the relay is starting to go it can cause that. The switch overrides the relay.
The auto headlights uses a relay, in the BCM, and if the relay is starting to go it can cause that. The switch overrides the relay.
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I have a Firebird so it only has manual control headlights. I can turn off the headlights whenever I want. Turning the switch and rotating the dimmer switch have no effect on the problem.
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Found this relay next to the hazard flasher module. Could this be it?? I unplugged it with no difference in headlight problems. Don't know where to find a spare.
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From: Jacksonville, FL (originally from Toronto Canada)
The following comments apply to US-model Firebirds only. Camaros and Canadian Firebirds have different light wiring due to the automatic headlight function controlled by the Daytime Running Light (DRL) module (not the BCM).
There is no relay for the headlights so you might as well plug that relay back in where you found it.
Do your highbeams work? The same power source and wiring is used for both highbeam and lowbeam up to the dimmer switch. Knowing this will really help narrowing down the source of the problem.
The fog lights and parking lights run off a completely separate power source than the headlights so the fact that they continue to work doesn't really tell us much for determining the headlight problem. It does indicate that the headlight switch is probably not bad.
A first guess from your description would be that there is a loose or damaged wire behind the headlight switch. I recommend you pull the switch out (leave the connector plugged in) and wiggle the wires to see if you can reproduce the problem.
There is no relay for the headlights so you might as well plug that relay back in where you found it.
Do your highbeams work? The same power source and wiring is used for both highbeam and lowbeam up to the dimmer switch. Knowing this will really help narrowing down the source of the problem.
The fog lights and parking lights run off a completely separate power source than the headlights so the fact that they continue to work doesn't really tell us much for determining the headlight problem. It does indicate that the headlight switch is probably not bad.
A first guess from your description would be that there is a loose or damaged wire behind the headlight switch. I recommend you pull the switch out (leave the connector plugged in) and wiggle the wires to see if you can reproduce the problem.
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Thanks, the high beams do in fact work. Only the low beams do not come on.
Ok, I have the dashboard torn apart and I have the switch out. I will wiggle the wires a bit right now and see if that fixes it.
Ok, I have the dashboard torn apart and I have the switch out. I will wiggle the wires a bit right now and see if that fixes it.
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Looks like it is something around the aftermarket alarm system box (or the box itself), cause when I wiggle it, I hear the shorting sound and the low beams work/don't work. It's all wrapped up tightly and tangled together so it's tough to work on it. Thanks, security installer.
I took the light switch apart and the only suspicious thing was a fine layer of oxidation on the copper contacts for the headlight switch (not dimmer), so I cleaned that off but it didn't fix the issue.
I took the light switch apart and the only suspicious thing was a fine layer of oxidation on the copper contacts for the headlight switch (not dimmer), so I cleaned that off but it didn't fix the issue.
Last edited by ZexGX; Feb 15, 2009 at 12:06 PM.
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Staging Lane
Joined: Apr 2007
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From: Macungie, PA
i came home while it was dark out a day or 2 ago and my headlights were working fine, then 2 hours later i go to go back out and i have no low beams, but my high beams are working fine. both bulbs couldnt have gone at the same exact time, i put these headlights on about a year ago. i checked the fuses also and nothing, i suppose ill have to look over the wiring as well.
edit: took apart the dash to check the wires behind the switch, they all seemed fine i straightened them out and messed with them, put everything back together and believe it or not the low beams worked again....but then i had no turn signals, 1 min later i get turn signals again, but back to no low beams....
edit: took apart the dash to check the wires behind the switch, they all seemed fine i straightened them out and messed with them, put everything back together and believe it or not the low beams worked again....but then i had no turn signals, 1 min later i get turn signals again, but back to no low beams....
Last edited by justmetk11; Feb 16, 2009 at 02:39 PM.
