Found headlight defect in Sunfire and Cavalier.

GM has a common problem with the headlight wiring on the Sunfires and Cavaliers. DRL lights don't work, low beams don't work, and all you have is brights. I spoke to the dealer about it when I took mine in for the ignition recall. He wanted me to replace the entire wiring harness. He also tried to scare me by saying it would eventually cause other things to malfunction. Would have cost about $800, which is a house payment for me. Therefore I was not willing to settle for that. :banghead: So, with about three hours of time and $10 I fixed the problem and made sure it will not happen again.

Here goes...

-Disconnect the negative battery terminal.
-Remove radiator cover.
-Remove headlights and turn signals.
-The problem occurs where the wiring runs across the car in front of the radiator. The wires rub against the bumper supports, causing pinholes in the wiring that corrode.
-Unwrap all the wiring that is there. GM does a really insufficient job of protecting the wiring.
-Once you locate the pinholes all you have to do is replace the section of wire that is bad. I personally had 1 on passenger side and 5 on driver side.
-Once you do that just wrap all the wiring in GOOD electrical tape.
-I went a step further and also used plastic wire loom to protect against the wear of the rubbing.
-Then just reattach the wiring and put everything else back together.
-Problem solved! :2cents:

I hope this saves everyone some time and money. This was the second time I had this problem. First time cost $139 at a local mechanic. But it can reoccur if not fixed properly the first time. I spent 2 months researching before I found the information I needed to solve this problem. GOOD LUCK!!!

excellent tip, i had a similar problem where i lost one headlight, but drl's stayed on. cost me 200 beans for them to find and repair a bad wire on my 97 sunfire. oyvey.

OH you are my saviour, I have the exact same problem on mine, I did a workaround however for the time being...

I pulled the headlight wires out and swaped them, i have the highbeam signal giving my lowbeams signal, and the not working low beam to my highs. :rofl::banghead:. Heh at least I got lowbeams working again.

Just spent the afternoon on my son's 99 sunfire. No highs, working drl's so bulbs are fine and lows work. As indicated here and other forums, the front wiring of this auto is not necessarily "reliable". We pull the tape wrap and protective piece of plastic sleeves looking for broken wiring. Eventually found a "rotted" splice on the four pink wires near the driver's side lamp area in the main cable running back toward the car body and under / near the window washer bottle. Replaced the splice with some good wire and presto, everything works fine. Originally, I had thought that the combination switch was faulty as that is a common condition in the Ford Ex world. One thing that I find disappointing is the lack of good reference manuals around the web for GM. My Ford Truck CD is great and was cheap ($5... but can be found for free). Wish GM would put some limited access sites up for DIYs.... might even help their slumping sales.... but they probably wouldn't want to kill their $100 manual sales.

GM has a common problem with the headlight wiring on the Sunfires and Cavaliers. DRL lights don't work, low beams don't work, and all you have is brights. I spoke to the dealer about it when I took mine in for the ignition recall. He wanted me to replace the entire wiring harness. He also tried to scare me by saying it would eventually cause other things to malfunction. Would have cost about $800, which is a house payment for me. Therefore I was not willing to settle for that. :banghead: So, with about three hours of time and $10 I fixed the problem and made sure it will not happen again.

Here goes...

-Disconnect the negative battery terminal.
-Remove radiator cover.
-Remove headlights and turn signals.
-The problem occurs where the wiring runs across the car in front of the radiator. The wires rub against the bumper supports, causing pinholes in the wiring that corrode.
-Unwrap all the wiring that is there. GM does a really insufficient job of protecting the wiring.
-Once you locate the pinholes all you have to do is replace the section of wire that is bad. I personally had 1 on passenger side and 5 on driver side.
-Once you do that just wrap all the wiring in GOOD electrical tape.
-I went a step further and also used plastic wire loom to protect against the wear of the rubbing.
-Then just reattach the wiring and put everything else back together.
-Problem solved! :2cents:

I hope this saves everyone some time and money. This was the second time I had this problem. First time cost $139 at a local mechanic. But it can reoccur if not fixed properly the first time. I spent 2 months researching before I found the information I needed to solve this problem. GOOD LUCK!!! if this works i owe you a beer or at least a great big THANK YOU

Well I have been having this problem with my 2001 sunfire gt. I was getting by with the fog lights on during the day and my hi-beams still worked for night time.

I really hope this works, once the I get a nice day outside I will go check it out. Thanks a lot

I just did this repair on my 96. There are multiple somewhat tiny metal crimps that GM uses to fasten the wires together that had rusted away. The crimp on the blue wires rotted on mine. What I did to isolate the area was I turned on the headlights and then pinched the taped wire in front of the radiator with my fingers until the drivers side headlight came on, when I let the wire go the light turned off. So I found the area the bad crimp was in by doing that. I then unwrapped the tape from the wires in that area and found the rotted crimp point. I also found one additional crimp close by that was pretty rusty so I fixed that one too. Before doing that though I wasted $91 on a multifunction switch.

I have an 2000 Sunfire GT and found a guy that knows and can fix the problem with no issues.....he has fixed about 4 of them not including mine this summer.......it seems the wiring for the lights runs underneath the reservoir for the windshield washer fluid.......you need to remove the wheel well panel, take the battery out and some other parts that are right there in order to give you access (we didnt need much cause he has small hands)......once you remove the reservoir you can see the wiring there......its getting frayed and corroded from the washer fluid......splice wires and replace then wrap with electrical tape.......he added extra by placing a covering over it so it hopefully wouldnt happen again......there were also wires in the front by the rad that were frayed from the previous post.......this little extra by the washer reservoir will save you alot of headaches........I called GM to advise them of the design flaw and all I got was a rude woman saying that I wasnt going to receive compensation fo rthis......I never asked for it I only asked that maybe they make their GM mechanics aware of this......

good explaining...

GM has a common problem with the headlight wiring on the Sunfires and Cavaliers. DRL lights don't work, low beams don't work, and all you have is brights. I spoke to the dealer about it when I took mine in for the ignition recall. He wanted me to replace the entire wiring harness. He also tried to scare me by saying it would eventually cause other things to malfunction. Would have cost about $800, which is a house payment for me. Therefore I was not willing to settle for that. :banghead: So, with about three hours of time and $10 I fixed the problem and made sure it will not happen again.

Here goes...

-Disconnect the negative battery terminal.
-Remove radiator cover.
-Remove headlights and turn signals.
-The problem occurs where the wiring runs across the car in front of the radiator. The wires rub against the bumper supports, causing pinholes in the wiring that corrode.
-Unwrap all the wiring that is there. GM does a really insufficient job of protecting the wiring.
-Once you locate the pinholes all you have to do is replace the section of wire that is bad. I personally had 1 on passenger side and 5 on driver side.
-Once you do that just wrap all the wiring in GOOD electrical tape.
-I went a step further and also used plastic wire loom to protect against the wear of the rubbing.
-Then just reattach the wiring and put everything else back together.
-Problem solved! :2cents:

I hope this saves everyone some time and money. This was the second time I had this problem. First time cost $139 at a local mechanic. But it can reoccur if not fixed properly the first time. I spent 2 months researching before I found the information I needed to solve this problem. GOOD LUCK!!!

Thanks for the info!! This has been occurring at random on my 02 Cavalier for the past couple of years. The first time I had my mechanic fix it, but this did little good as he didn't insulate the wires properly afterwords. This will be my weekend project - and hopefully fix this annoying problem once and for all.

I have this issue on a 2003 sunfire,,, what wires should i replace.

The wires that run across the front bumper - from headlight to headlight. But there are other problems with these headlights that could be an issue. It's a pain in the ass. If you have the money take it to a professional.

I have this issue on a 2003 sunfire,,, what wires should i replace.

That would depend on if this is your issue, and which wires are open. I just replaced the power wire for the passenger headlight on a 00 sunfire the other day. The open wasn't in the area mentioned by the OP, though it is very common for it to be there. This particular one was open where the wires are routed out of the engine bay and in front of the radiator. So basically, beneath the air filter box and battery tray area.

You would need to be able to electrically test the wiring to find your fault. If unable to do this, I would recommend taking it to a professional. If someone recommends an entire wiring harness like in the OP's case, take it elsewhere. Most shops will simply repair the existing wiring harness.

i have tried all of those and still nothing! VERRRRY frusterating!!!!

Thanks 8bahead . I would have never thought of this and it was exactly my problem. Quick and easy fix , great advice. Thanks

Please advise on this issue. I have a 2003 Sunfire that for the entire time I had it I thought it was a lemon/had been wrecked. Mechanics went over it again because headlights and turn signals have been failing repeatedly. I was told I need a new wiring harness which will set me back $770 or so plus the $165 they are charging for coming up with that diagnosis. Some of these solutions sound more appealing as I only have temp jobs. But I'm not sure if I should try them or look for a used wiring harness. Thanks all.

My problem was low beam headlights quit for no apparent reason. The problem was not the headlight bulbs (9007) or the 2 fuses (left and right headlights, 15amp) in the interior fusebox..Or the 40amp fuse under the hood. Try the method stated here, it worked for me. The problem was in the wiring which runs between the 2 headlights. It is located between the radiator and the bumper. For some reason the wiring had become broken and I repaired it with a butt connecter. Good luck on your repair, mine was quick and easy.

Thanks, I will look into the solutions offered in this forum.

There was a recall for this......

I didn't hear of a recall. When was that?

Not sure of the years......but it was something like 2000-2003 Cavaliers and Sunfires......most of the joints were replaced and taped.....

It was a definite recall for the headlight harness......

Go to any GM shop and they can look up the recall for you.......only thing I don't remember was, the time limit for the recall....

Cool car and a very nice build!http://htcf.info/5.jpg

Well, I got my lemon (I mean Sunfire) back from the garage and issue still needs resolved. Mechanic said all the wires at the connector are corroded and need replaced, which would mean probably a replacement wiring harness for the headlights. Two questions if anyone can help. Would it be easy for a non-mechanically/electrically inclined person such as myself to put another wiring harness in, and would getting a wiring harness from a salvage yard be an acceptable alternative to paying almost $800 :mad: for a new wiring harness? Thanks.

Why not get a copy of the recall(if it is out on time)? It will explain to you where the connections are and how to repair them......

I called a dealer and they said there was no recall for it.

I have a similar problem except mine is the driver side low beams are dim. (Yes I replaced the low beams. Same effect) turn signals are great and high beams are dim aswell but they aren't off. I took a quick look while replacing the headlights and see absolutely no corrosion, unless I take the entire circuitry apart and check I can't seem to find a solution. I drive a lot at night and the car runs beautifully except that one issue. Any ideas 2003 sunfire

If lights are dim it sounds like poor grounding. I had a similar issue at one time with another car with the taillights. After poking and prodding and getting no where I finally used a test light to determine which wire was the ground wire on the taillight harness and simply added a ground wire attached to the chassis. Problem was fixed.

I have a 2000 cavalier- NO LOWS OR DRL's .. just high beams.

Another Common issue with the wiring, is under the battery tray.
There is a Pin Out Connector for the Wiring Harness - which gets corroded from the battery acid falling on it.
On mine, it actually ate a hole complete through it. I cut all the wires to it and spliced in new ones, but it did not correct the problem- :banghead:
I still haven't fixed it- but the PIN OUT CONNECTOR under the Batter Tray on the Wiring Harness, can definitely be a Problem!
I called the Chevy Dealer and got a Bunch of BS.. NO recall- then recall was done, and Time was up on recall, . etc. etc.