Numerous headlight problems on 91 'bird

[JimRochester]

My son is away in the ARMY and while he is away I am trying to fix what seems to be numerous headlight problems. I did search and read several of the threads but I seem to have some compounded problems not listed.

problem 1: right headlight motor was replaced with a new one but once installed will not move either under power or manually. It's stuck so I yanked that out.

problem 2: the right side does not seem to be getting power. The drivers side headlight works but when switched to the passenger side will not, leading me to believe there is no power on that side at all?

problem 3: the drivers side headlight will go on but the motor will not go up and down. You can raise it manually unlike the pass. side but I need them to work. Do both motors need to be working in order for it to function?

So basically I have one headlight that will light but neither motor is working for two different reasons.

Please help. Where do I start?

[JimRochester]

Update:

I got the passenger side headlight working. So there is power over there

The passenger side motor which was the new one installed will rotate via the knob on top, the drivers side will not however the light can be pulled up and down manually on that side

I grabbed a circuit tester and so far have not found juice running to the either motor. They appear to have been a homemade crude wiring.

Still need any recommendations. Thanks

[aleekat]

I rewired headlights using this link. Find the hot wire from the switch and go from there.
http://www.classictruckshop.com/club...ead/lights.htm

[JimRochester]

Anyone have anything on rewiring the motors themselves? I've gpt the headlights working but the motors are getting no juice. I checked all the fuses and they seemed good. Any areas or relays that could be a problem?

[Tech II]

Power to the headlight motors comes from the headlight door module.....power to operate the motors comes from fuseable links, and the module uses inputs from the headlight switch....

So basically you check for power from two legs of the fuseable links, check for module ground, and check for signals from the headlight switch(2).....if these check out, need a module....need a schematic...

[JimRochester]

Well it looks like I'm getting closer. I grabbed a manual off ebay for the fuses since I was flying blind. The manual shows a separate "convenience center" which has the fuseable links for the motors. Where the hell is that convenience center? There's nothing right next to the fuse box. I checked the passenger side and under the hood with no luck but I don't know what I'm looking for. Somewhere along the line someone did some homemade wiring but I'm assuming they didn't take that out. Appreciate everything up to now. Just a bit more and I should have it.

[Blue Bowtie]

The "Convenience Center" is under the I/P, and swings outward and down. I contains the switching transistor for the I/P lighting dimmer, the flashers, the annoying key/seatbelt/door warning chime module, and on earlier models the fuse links for the headlight doors.




1988 and later models eliminated the isolation relay and individual motor relays, replacing them with the infamous headlight door module on the firewall behind the brake power booster. '88-later cars with the module should have had individual 15A circuit breakers or fuses for each headlight door motor instead of the fuse links, being marked HDLP DR#1 and HDLP DR#2. I know that '90-up used fuses in the Convenience Center:



I would be good to verify ALL grounds, including those around the battery and headlight motors.

[JimRochester]

Can someone tell me what I'm missing? Nothing under the dash and there are three things behind the brake booster but none seem to be any type of fuseable link.

http://home.earthlink.net/~schrader4...s/100_1582.JPG

http://home.earthlink.net/~schrader4...s/100_1583.JPG

[Blue Bowtie]

If you have the lower IP bolster removed there should be a swing-down panel just to the left of the radio. If it isn't there the fuses may be in the main fuse panel.

[JimRochester]

Found the center. Found the fuses. Replaced the fuses. Getting juice to the connection. No motors working. Son of a b....h. Now what do I look for?

One motor we installed last year as a NOS, the other is an older one but always worked before. Do I need to replace both? Is there a way to test them outside the car, or direct from the battery?

Thanks to everyone by the way. Definitely making great headway from where I started.

[Tech II]

Post #5.....

You can go Autozone.com, register, and get a schematic for your headlights.......disconnect the harness to the module and you can power the headlights at the harness(to check circuit and motors)......like I said, you check for power and ground at the harness, and inputs from the headlight switch....if all ok, you need a module.....

[Blue Bowtie]

Originally Posted by JimRochester

Found the center.

It's a good thing they call it a "Convenience Center" isn't it? That's the only convenient thing about it.

Originally Posted by JimRochester

... Found the fuses. Replaced the fuses. Getting juice to the connection. No motors working. Son of a b....h. Now what do I look for?

One motor we installed last year as a NOS, the other is an older one but always worked before. Do I need to replace both? Is there a way to test them outside the car, or direct from the battery?

Thanks to everyone by the way. Definitely making great headway from where I started.

If you turn the manual knob to raise the headlight door does the motor try to run it back down? If so, the end limit switches in the motor(s) or the control module may have a problem.

As previously suggested, it would be best to get your hands on a schematic so you can see exactly what is supposed to be going on there.

[JimRochester]

Originally Posted by Blue Bowtie

It's a good thing they call it a "Convenience Center" isn't it? That's the only convenient thing about it.

If you turn the manual knob to raise the headlight door does the motor try to run it back down? If so, the end limit switches in the motor(s) or the control module may have a problem.

Doesn't do anything. No noises, sounds or movement. They act like they are not getting power but I checked and the light on my meter lit up just fine. I did try raising them to see if they would lowere when turned off but no go on that too.