Headlights kill dashlights-wtf?
I have ask the stupid question...did you check your dimmer adjuster/switch. Maybe you bumped it while you and the gf were ummm 'having some fun'.
Also, provide more detail, like are you blowing fuses, did you change something and this problem started, etc.
Also, provide more detail, like are you blowing fuses, did you change something and this problem started, etc.
This happened to me every time I would let the e-brake down and the headlight would turn on the dash lights go out. I just replaced the fuse on the dimmer switch on the side panel by the door and everything worked fine.
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From: Roseville, Ca.
Thanks...I checked that. Not blowing fuses. Removed all wiring for aftermarket stuff. And yes, I changed the engine. I've already rechecked the grounds.
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i dont know anything....but what i do know is im about to throw in a 408 so if this happened after an engine swap.......my eyes are peeled to this thread....
Last edited by DGageSS; Jun 2, 2009 at 03:01 PM. Reason: add three words
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My personal opinion....electricity takes the path of least resistance. If the headlights are off, the pwr is going to the dash, when the headlights turn on....maybe there is enough resistance somewhere in the ciruit that it is being diverted away from the dash circuit. I would get a meter and start checking resistance. You shouldn't be over a couple of ohms period on any straight wire....even on splices if done correctly. Start where the two circuits connect and then read resistance from that point to each end and see what the meter is reading. Any anomoly in resistance (other than passing through a switch) should be a good indication of where the problem MAY be.
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From: Roseville, Ca.
My personal opinion....electricity takes the path of least resistance. If the headlights are off, the pwr is going to the dash, when the headlights turn on....maybe there is enough resistance somewhere in the ciruit that it is being diverted away from the dash circuit. I would get a meter and start checking resistance. You shouldn't be over a couple of ohms period on any straight wire....even on splices if done correctly. Start where the two circuits connect and then read resistance from that point to each end and see what the meter is reading. Any anomoly in resistance (other than passing through a switch) should be a good indication of where the problem MAY be.
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just so we are on the same page....
http://www.tafmotorsports.com/images...g.diagrams.pdf
Page 25 is a great place to start.
http://www.tafmotorsports.com/images...g.diagrams.pdf
Page 25 is a great place to start.
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Thanks...I got them a while back when I was working on my RX-7. I decided to relocate the PCM to behind my seat so I needed about 8 extra feet of wire. I could have just cut and spliced wires....but instead I made an entire engine harness from scratch using shielded wire. All Aero-space spec wire at that. That harness should outlast my car. Those schematics really came in handy. I NEVER want to do that again.....whoever designed the LS1 engine harness is a friggin tard. They had ground splices everywhere. About your problem though, if you look on page 25 in the upper right hand corner about 3 inches down and 2 inches inboard you will see (dash harn, near headlamp switch and cluster breakouts) S226. That is splice 226 and that is where your instrument cluster system apparently ties in with a CRAP load of other stuff. The problem with wiring is that it's almost never the crazy stuff and usually something simple like a fuse..........until YOU have the problem.
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thanks for taking the time...I'm a telco cable splicer, so I know a little about dc stuff, but absolutely NOTHING about auto stuff. The drawings I can at least relate to a little. Thnx again!
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Hey Bennie,
Thanks for the diagram. Not sure if you're still out there, but the section you describe makes some sense. I'm still a little stumped. I'm trying to think if there was an event involved with my engine swap. I did have the console out. I might have grounded a wire or broken one while I was screwing around. I also have my e-cutout wired in the cigarrette lighter on a non illuminated momentrary toggle that had a frame ground at one time.
I see that the circuit in question comes from the fuse panel, in and out of the bcm via a theft relay...I wonder if that's near the airbag module near the shifter? And the s226 at the cluster break outs is a splice, right? What is the dotted line going back to the s211 switch and relay? I inspected everything under the console last night and I did reconnect the e-brake switch which was loose. I swapped each fuse momentarily inside and underhood(not the big ones) with higher amperage fuses with no results. Could I have smoked a relay? Smashed a wire? I notice that the dash and radio lights dim very quickly, not switch off. Like they're having the life sucked out of them.page 29 seems more relavent.
Thanks for any help.
Thanks for the diagram. Not sure if you're still out there, but the section you describe makes some sense. I'm still a little stumped. I'm trying to think if there was an event involved with my engine swap. I did have the console out. I might have grounded a wire or broken one while I was screwing around. I also have my e-cutout wired in the cigarrette lighter on a non illuminated momentrary toggle that had a frame ground at one time.
I see that the circuit in question comes from the fuse panel, in and out of the bcm via a theft relay...I wonder if that's near the airbag module near the shifter? And the s226 at the cluster break outs is a splice, right? What is the dotted line going back to the s211 switch and relay? I inspected everything under the console last night and I did reconnect the e-brake switch which was loose. I swapped each fuse momentarily inside and underhood(not the big ones) with higher amperage fuses with no results. Could I have smoked a relay? Smashed a wire? I notice that the dash and radio lights dim very quickly, not switch off. Like they're having the life sucked out of them.page 29 seems more relavent.
Thanks for any help.
Last edited by Steve Gunn; Jun 3, 2009 at 12:27 PM.
i doubt its your problem, but my dimmer switch was just bad, anytime i would turn my dome light on the dash would go out........it ended up just being the wheel switch. but its pluged into the headlight switch. i would try changing it for a few bucks and seeing if its that simple.