1990 headlight relay
Thread Starter
4th Gear
Joined: Nov 2005
Posts: 4
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1990 headlight relay
I just replaced the bushings on the left side headlight and it works great, I had to have the motor rebuilt on the passenger side, but after I hooked everything up it doesn't work. I can supply power directly to the motor and it will work, someone said it may be the relay located on the drivers side. What does it look like and how do I know if it is bad? Or is there possibly another problem?
Melting Slicks
Joined: May 2004
Posts: 2,524
Likes: 10
From: Lufkin Texas
St. Jude Donor '05-'06
Check your fuseable links at the power distribution block down low behind the battery. Power for headlights is provided by links marked F and G. If they are fine then I would suspect headlamp control module. There are no relays on the 90 for headlamps. Let me know if the links are ok and I'll give you a pic of the control modules location.
I bet it's a link.
I bet it's a link.
Thread Starter
4th Gear
Joined: Nov 2005
Posts: 4
Likes: 0
Wellll
Well I am going to show my ignorance. I am going to look again tommorow when I have more time, but I am not sure where the fuses are. I know you said low behind the battery, but all I saw was two wires going into a what looked like a connector. Am I close?
Melting Slicks
Joined: May 2004
Posts: 2,524
Likes: 10
From: Lufkin Texas
St. Jude Donor '05-'06
You may have to remove your battery to get at them but there is a post with several fuseable links down near the base of the battery inbetween the battery and firewall. If you have an owners manual in your glovebox it refers to this as the battery jump start post. The fuseable links look like a wire with a small buldge in it like a snake that has eaten a mouse. Usually when they are blown they will have a seperation but sometimes not. You really just need a test light to check for power on wire beyond the link.
The buldge is where the letter is marking whats what. As stated earlier, the ones for headlights are F and G.
Napa auto parts stores carry the fuseable links but you can also replace them with a standard in line fuse of same amperage rating if needed.
I'm not at home now but if needed, this afternoon I can take a pic of mine for you. Let me know if you need it.
Dave
The buldge is where the letter is marking whats what. As stated earlier, the ones for headlights are F and G.
Napa auto parts stores carry the fuseable links but you can also replace them with a standard in line fuse of same amperage rating if needed.
I'm not at home now but if needed, this afternoon I can take a pic of mine for you. Let me know if you need it.
Dave
Melting Slicks
Joined: May 2004
Posts: 2,524
Likes: 10
From: Lufkin Texas
St. Jude Donor '05-'06
Ok, here's the power distribution post where your fusible links are located. As you can see by all the inline fuses on mine I also use it for power for my nitrous set up and bottle heater and such. The fuseable links are the ones below those and are dirty orange in color. You can only see one of mine clearly at about 4 o'clock going down at the bottom under those 2 yellow wires that go to 20 amp fuses. The rest are under there but blocked by my other inline fuses.
While I'm at it, here's a pic of the headlight control module and it's location in front of the drivers side wheel well.
While I'm at it, here's a pic of the headlight control module and it's location in front of the drivers side wheel well.
Thread Starter
4th Gear
Joined: Nov 2005
Posts: 4
Likes: 0
90-headlight
Dave: Thanks for the pics. We checked the fuseable links and there were no visable buldges or breaks in the wire. Mine doesn't have any exchangeable fuses, only hard plastic tube with a wire going in each end, but they looked fine. We then checked the continunity of the green and gray wires coming from the control module to each of the headlight motors, there was no broken wires.
So should I take off the control module and open it up? Or what next?
So should I take off the control module and open it up? Or what next?
Melting Slicks
Joined: May 2004
Posts: 2,524
Likes: 10
From: Lufkin Texas
St. Jude Donor '05-'06
Thats where I would check next. Dont dont open it up. It's solid state so if it turns out to be bad you'll probably just have to replace it. Take a test light and probe the two red wires going into the control module. They should be hot always. If not then one of your fuseable links is bad even though it looks good.
I got lucky and solved my 90's problem when I found a blown fuseible link so I didn't have to go further. I guess from this point on I would just follow the book.
Here's the wiring diagram from my helms manual.
Here's the trouble shoot guide.
Sorry, my scanner is broke so I just had to photgraph the pages. I hope this helps. Good luck.
I got lucky and solved my 90's problem when I found a blown fuseible link so I didn't have to go further. I guess from this point on I would just follow the book.
Here's the wiring diagram from my helms manual.
Here's the trouble shoot guide.
Sorry, my scanner is broke so I just had to photgraph the pages. I hope this helps. Good luck.
Last edited by skateparkdave; Jun 2, 2006 at 02:37 PM.
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