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Both headlights won’t open.

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Old 04-24-2021, 02:47 PM
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4speedC4
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Default Both headlights won’t open.

Hello again everyone,

I’ve recently discovered that now both of my headlights do not open and do not even attempt to move when the switch is pulled. Both headlights will retract if I plug the motors back in after I manually open them. It also seems like all relays are clicking when the headlight switch is pulled. Not sure where to go from here lol, both headlights worked last year, then the right side stopped, now both don’t work.

Any input/suggestions on how to tackle this next would be greatly appreciated.
Old 04-24-2021, 03:24 PM
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xrav22
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A man at an auto show told me(who made them at Van Nuys CA plant) just turn the little wheel back and forth 1/4 in a few times. Worth a try. It has worked for me for 7 years.
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4speedC4 (04-24-2021)
Old 04-25-2021, 12:15 PM
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Originally Posted by xrav22
A man at an auto show told me(who made them at Van Nuys CA plant) just turn the little wheel back and forth 1/4 in a few times. .....
Last time I got a state inspection, inspector told me my car failed as one headlight wouldn't open. I was quite surprised as I'd never had a problem (don't drive it much at night). Walked out to service bay, popped open hood, opened and closed light manually, worked fine then and passed inspection. As per previous poster, worth a try.
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4speedC4 (04-25-2021)
Old 04-25-2021, 01:06 PM
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4speedC4
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Just went out and tried, cranked them back and forth to no avail. Nothing with this car is ever that simple! Lol. It seems to me that the switch has gone bad, which I know is a PIA to replace. Thanks for your suggestions and I’ll post back here if/when I get it figured out.
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Snakecharmer383 (06-01-2021)
Old 04-25-2021, 09:51 PM
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ThatOneKid
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Sounds like a wiring issue or a failed relay, to test the light switch disconnect the isolation relay, if you have 12V on the yellow wire with the switch pulled, and a few volts to 0 volts with it pushed in the switch is good. I had the same issue with my 85 when I first bought it and it was the relays, not the switch.
The relays are absurdly expensive and are set up so each headlight has its own relay. I'm not a fan of that because you get unique failures where one works normally and the other doesn't. I personally cut the relays out and wired in three 40A automotive relay sockets, instead of right, left and isolation relays, I use an up, down and, isolation relay, and the entire setup cost me less than replacing one of the stock ones
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4speedC4 (04-26-2021)
Old 04-26-2021, 12:44 PM
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Originally Posted by ThatOneKid
Sounds like a wiring issue or a failed relay, to test the light switch disconnect the isolation relay, if you have 12V on the yellow wire with the switch pulled, and a few volts to 0 volts with it pushed in the switch is good. I had the same issue with my 85 when I first bought it and it was the relays, not the switch.
The relays are absurdly expensive and are set up so each headlight has its own relay. I'm not a fan of that because you get unique failures where one works normally and the other doesn't. I personally cut the relays out and wired in three 40A automotive relay sockets, instead of right, left and isolation relays, I use an up, down and, isolation relay, and the entire setup cost me less than replacing one of the stock ones
I will definitely be trying this over the weekend if I have time. More in my realm of abilities instead of taking a fragile 35 year old dash apart to replace a switch that may not even be bad. I’ll post an update. Thanks!
Old 04-26-2021, 01:39 PM
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I got tired of having headlight issues all the time. So I removed the isolation relays all together. I got a very nice simple relay/fuse box off ebay and rewired it myself. I installed a very small toggle switch that controls the head light motors (2 five pin relays) and I used the factory pull switch to turn the bulbs on. No isolation relay, no ripple current relay and no limit switches. Now it works every time. Just take your finger off the button when it's up or down all the way.
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4speedC4 (06-01-2021)
Old 04-27-2021, 02:48 PM
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kael
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Originally Posted by ThatOneKid
The relays are absurdly expensive and are set up so each headlight has its own relay. I'm not a fan of that because you get unique failures where one works normally and the other doesn't.
Speaking as engineer, worst case is the likely reason. With separate relays, a failure results in loss of one headlight, not both at the same time.
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4speedC4 (06-01-2021)
Old 04-27-2021, 08:14 PM
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Originally Posted by Phobos84
I got tired of having headlight issues all the time. So I removed the isolation relays all together. I got a very nice simple relay/fuse box off ebay and rewired it myself. I installed a very small toggle switch that controls the head light motors (2 five pin relays) and I used the factory pull switch to turn the bulbs on. No isolation relay, no ripple current relay and no limit switches. Now it works every time. Just take your finger off the button when it's up or down all the way.
Interesting solution.

Originally Posted by kael
Speaking as engineer, worst case is the likely reason. With separate relays, a failure results in loss of one headlight, not both at the same time.
Oh cool, same here, the OEM DPDT relays are more failure-prone compared to a modern heavy-duty SPDT relay not to mention the SPDT relay comes in at a fraction of the cost, and a smaller package. While the SPDT relays may be a SPOF, it's a much more robust solution that will last much longer than the OE relays for less than the cost of an OE replacement. Not as elaborate or cool a solution as stock, but a 40A waterproof relay will last much longer the OE ones and is available at your local parts store, it'll be easier to replace than the fusible link.

Last edited by ThatOneKid; 04-27-2021 at 08:19 PM.
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4speedC4 (06-01-2021)
Old 06-01-2021, 09:28 AM
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Originally Posted by kael
Speaking as engineer, worst case is the likely reason. With separate relays, a failure results in loss of one headlight, not both at the same time.
Sorry for the delay in response everyone, got tied up with work and finals week in college and didn’t get to work on it until last week. After struggling to get the relays out, I discovered they were all corroded to hell. Bought and replaced all three relays and cleaned up the connectors with contact cleaner and headlights work like a charm now! Definitely not the problem I thought it would be but hopefully this helps someone else out there. Thanks everyone for your assistance.
Old 06-01-2021, 11:25 AM
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xrav22
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Did you happen to take a pic of the final setup with the new relays. I have one high beam out and I suspect the old relays.
Thx
Old 06-01-2021, 02:28 PM
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Originally Posted by xrav22
Did you happen to take a pic of the final setup with the new relays. I have one high beam out and I suspect the old relays.
Thx
The Relays are only for the Headlight Motors, they are not involved with illumination.
Old 06-01-2021, 07:59 PM
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Originally Posted by 4speedC4
Hello again everyone,

I’ve recently discovered that now both of my headlights do not open and do not even attempt to move when the switch is pulled. Both headlights will retract if I plug the motors back in after I manually open them. It also seems like all relays are clicking when the headlight switch is pulled. Not sure where to go from here lol, both headlights worked last year, then the right side stopped, now both don’t work.

Any input/suggestions on how to tackle this next would be greatly appreciated.
I don't know if you saw my post about my headlights but it's been a complete nightmare as always with the car. Changed the gears now one opens and works and the other doesn't. Ordered a motor so that's the next thing to try I guess.

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