First let me say that I have looked through many of your posts and I tried finding this info but I couldn't. Sorry if I am repeating a previous issue.

My 1985 Firebird lost power to the headlight motors. The lights still come on but the motors are dead. The motors are new as I replaced them within the last year.

Replaced headlight switch
Replaced headlight relay by break booster
Replaced both relays near lights.

no luck.

I saw some people talking about a fuse BUT the owners manual says that the headlight are not on a fuse.

So, is there a fuse I can check? Or any other help would be appreciated.

 

After you replaced the motors "last year", did they work then or is this a new problem today? I would check the headlight grounds to the motors up front. 1985 does not have a Headlight Control Module, so not too much left to check.

 

The headlights were working fine after I replaced them. But now I have more info: I manually wound the lights up last week so I could drive her to my storage garage at night. When I turned off my lights, they actually closed. But when I turned the switch back on, they would not come back up. So they go down from the up position but they won't go back up.

 

I'm having the same problem with my '83. Try to slowly push on the headlight switch. It will move a small amount and then a stiff spot. right in I hold it there until they pop up, then I can push the switch all the way. I haven't figured out why this is yet, but I'm working on it. Maybe you have the same problem.

 

The relay that is up by the brake booster is for the foglights. There is a relay near the battery which is called the isolation relay. This supplies power to the two relays which actually power the headlight buckets. Now, there are fusible links in the wiring harness that feeds this relay. I found on my car that one or both were burned out. My car would do the same thing; I could manually crank them open and they would close on their own when the headlights were turned off.

The fusible links are located in the large harness on the driver side. It is in split loom and the links are near the cruise control motor. The wire should be red or red/wht. I replaced mine with pieces of wire. It all worked fine after that.

 

This is from my 86 manual,I'm pretty sure they are the same

 

I actually just fixed a similar problem mine had- they'd go up, but wouldn't go down on their own. After testing the isolation relay (between passenger headlight and battery, look directly behind the battery and you'll see it) and finding that I had no voltage when the switch was calling for the doors to go down, but I had voltage when it was calling them to go up, I turned to the switch.

The headlight switch has three prongs internally and kinda operates like a breaker. I assume the pressure of the cover mashes the switch levers down on the prongs, which in turn puts pressure on the prongs to make contact to complete the circuit... But after 30+ years, the plastic wears out. I fixed my problem by taking a small black zip tie, looping it around the switch housing, and cinching the dogsh*t out of it. Problem solved, my headlight doors work again. There's some NOS switches on eBay that I'm planning on getting soon but this will do for now.

I can take pics in the morning if you'd like a visual on what I did. Just let me know.

 

Your best bet is to check fuses, then get a test light and check power to the isolation relay and follow it from there

 

THANK YOU!! This is amazing! Not only solved one of my problems but The diagram I could not find also showed where my coolant sensors are located. Thanks!