My DRL's quit working, any ideas?

drperry

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When the sensor says the headlights are "off" the BCM automatically turns the DRL's back on...

Might have to do some wire tracing and find the DRL trip wire from the BCM...

Maybe you bumped something loose when you did the quad beam mod :dunno:
 

ScottyBoy

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When the sensor says the headlights are "off" the BCM automatically turns the DRL's back on...

Might have to do some wire tracing and find the DRL trip wire from the BCM...

Maybe you bumped something loose when you did the quad beam mod :dunno:

I did the quad beam mod over 3years ago, and the DRL's just started acting up sometime in the past 1 or 2 weeks. :dunno: I'll mess it later today if I get a chance.
 

drperry

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So its not that, then :lol:

Maybe your headlight switch is going out :dunno:

I know I can mess with my DRL's by tinkering with wires behind the switch :dunno:
 
B

Bernie

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No one else has suggested it so I will...

Are you sure the parking brake switch is working? I can't remember if there's a separate set of contacts (normally closed) in the switch for the DRLs or not, but if there is then it's possible that part of the switch is bad - or has a bad connection at the terminal.

Also, not sure when they changed it but on my '99 GMC the DRLs will come on anytime the parking brake is off and the key is on, no matter what gear you're in, so you should be able to check it with the tranny in park and the engine not running, so long as the key is on.
 

ScottyBoy

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No one else has suggested it so I will...

Are you sure the parking brake switch is working? I can't remember if there's a separate set of contacts (normally closed) in the switch for the DRLs or not, but if there is then it's possible that part of the switch is bad - or has a bad connection at the terminal.

Also, not sure when they changed it but on my '99 GMC the DRLs will come on anytime the parking brake is off and the key is on, no matter what gear you're in, so you should be able to check it with the tranny in park and the engine not running, so long as the key is on.

Not sure about the parking brake switch, but I do know for a fact that the DRL's don't come on till you put it in drive. They immediately go off if you put it back in park, or apply the parking brake. I've seen that happen on my truck when they were working. Is your 99 a newer body style or the older body style? :dunno:

And I didn't go mess with it today, we had very shitty weather and I didn't feel like doing anything outside. Its not like its gonna stop me from driving it or anything, so I'll dig deeper in diagnosing when I get more time, and better weather. No rush.
 
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Bernie

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Old body style, so it seems they changed how it works. I'd rather have your setup, since there's times you want to just sit in park but might not want to put the parking brake on.
 

ScottyBoy

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Ok. I'll post if I do find anything out though.

Or if I don't either:dunno: :lol:
 

Darkanion

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Actually, that parking brake thing might be feasible. Have you checked to see if the light comes on, on the dash, when you set the parking brake? That might tell you whether or not there's a problem with the switch on the parking brake.. :dunno:
 

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