Headlight Woes
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Joined: Jul 2004
Posts: 238
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From: Hawthorne, CA.
Headlight Woes
Headlights are doing strange things. Heading for work this am, started the car up and turned on the headlights, everything was fine. Stepped on the brake pedal and the headlights went out (stayed up). Turned headlight switch off, the lights retracted, turned the switch back on, the lights would not come up or on. Didn't have time to deal so took the other car to work. Came home and the same problem after starting the car. Repeatly turned on and off the light switch and ignition swtich. When I hit the brake pedal the lights stay on in accessory and start position (without the engine on) as soon as I start the engine the lights go out and stay out (the headlights stay in up position). When the engine is on and the lights are down, turn the light switch on and nothing happens. So basically it's this:
Engine Off - headlights come up and on (in accessory & start postions)
Engine On - if headlights currently up they go off (stay off)
Engine On - headlights will not come up
Hope this isn't too confusing. I've searched the archives and cannot find this same problem. Appreciate any help.
Engine Off - headlights come up and on (in accessory & start postions)
Engine On - if headlights currently up they go off (stay off)
Engine On - headlights will not come up
Hope this isn't too confusing. I've searched the archives and cannot find this same problem. Appreciate any help.
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From: Mountains of GA!
Ron - I had this EXACT same problem one time. It turned out to be a loose ignition switch connector...go figure...
Please add your car's MY and other particulars to your posts in the future, as oft-time - different years can have different solutions/answers.
Please add your car's MY and other particulars to your posts in the future, as oft-time - different years can have different solutions/answers.
Electron Wrangler
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From: Phoenix AZ
The headlights are complex!
I have no idea why the brakes caused the issue - could be ground issues maybe coupled with resisistance build up in the switch contacts or terminals.... For similar symptoms first I'd suggest cleaning grounds (for Pod & CE) and cleaning & reseating switch terminals and relay teminals - then finally swap the switch & relay out.
The light switch has 2 poles (2 seperate switches that operate together). These control the lights for side/parking lights & headlights as well as the operation of the headlight motors - all these via the headlight combination relay.
The pod motor has full-up/full-down limit switch feedback to the relay to stop driving up or down and also to turn the headlights on only after the pods are fully up. There is also a starter interlock that turns the headlight off when the starter is enaged. If any of these features malfunctions odd things start to happen....The brakes are not (normally) directly connected to any of this...
So for example when the headlights fail to come on it could be the fuse, the switch, the light relay,
the motor relay, the motor, the limit switch, the starter disable relay... more... You get the idea!
Alan
I have no idea why the brakes caused the issue - could be ground issues maybe coupled with resisistance build up in the switch contacts or terminals.... For similar symptoms first I'd suggest cleaning grounds (for Pod & CE) and cleaning & reseating switch terminals and relay teminals - then finally swap the switch & relay out.
The light switch has 2 poles (2 seperate switches that operate together). These control the lights for side/parking lights & headlights as well as the operation of the headlight motors - all these via the headlight combination relay.
The pod motor has full-up/full-down limit switch feedback to the relay to stop driving up or down and also to turn the headlights on only after the pods are fully up. There is also a starter interlock that turns the headlight off when the starter is enaged. If any of these features malfunctions odd things start to happen....The brakes are not (normally) directly connected to any of this...
So for example when the headlights fail to come on it could be the fuse, the switch, the light relay,
the motor relay, the motor, the limit switch, the starter disable relay... more... You get the idea!
Alan
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Joined: Sep 2004
Posts: 9,429
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From: Not close enough to VIR.
Originally Posted by Alan
So for example when the headlights fail to come on it could be the fuse, the switch, the light relay,
the motor relay, the motor, the limit switch, the starter disable relay... more... You get the idea!
Alan
the motor relay, the motor, the limit switch, the starter disable relay... more... You get the idea!
Alan
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Joined: Jul 2001
Posts: 3,291
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From: Midland, Texas
FWIW,
Having reflected on my sons', Zack, White 81', auto, and 'Pattycakes', my 82' Weissach constant
morphing light/wiring issues I'm going to start with new light switches, then ignition switches and finally just bypass the LCU - possible light bypass on the warn system as well if the LCU bypass doesn't work.
We have been front to rear; exhaust/heatshields dropped front and rear bumpercover, splash shields off. Console, pod, rear quarters, carpets,and light assembly's pulled fuse panel relay/fuse board out and cleaned. Continuity/draw checks, ground search and clean missions to include speaker grounds and the LCU's replaced. Master brake cylinder/dual brake switch replacement.
I am hoping it's the Ignition/light switches.
We love our sHARKs but these constant /varying warns with no apparent real issue, or sets of lights dropping off line is getting old.
Will advise after step by step swaps/bypass surgery's.
Good call, MArk.
Alan, How well I know ...
Having reflected on my sons', Zack, White 81', auto, and 'Pattycakes', my 82' Weissach constant
morphing light/wiring issues I'm going to start with new light switches, then ignition switches and finally just bypass the LCU - possible light bypass on the warn system as well if the LCU bypass doesn't work.
We have been front to rear; exhaust/heatshields dropped front and rear bumpercover, splash shields off. Console, pod, rear quarters, carpets,and light assembly's pulled fuse panel relay/fuse board out and cleaned. Continuity/draw checks, ground search and clean missions to include speaker grounds and the LCU's replaced. Master brake cylinder/dual brake switch replacement.
I am hoping it's the Ignition/light switches.
We love our sHARKs but these constant /varying warns with no apparent real issue, or sets of lights dropping off line is getting old.
Will advise after step by step swaps/bypass surgery's.
Good call, MArk.
Alan, How well I know ...
