A common issue with C4 Corvettes is the headlight motor no longer working correctly. It can be struck open or closed or half-way. Typically, the cause is the nylon gear getting worn down or even breaking. You won’t really know what is wrong until you actually get the motor out of the car to see what the problem is. Here is the step by step process to get the motor out and then see what needs to be fixed. You can always just buy a new one if you like but that will set you back about $300. My recommendation is to figure out what the problem is first and then go from there. This might not be an option if you frequently drive your C4 or even daily drive since it will take a while to get a new motor or part in.
This is really a pretty easy fix. I believe anyone with some sort of repair knowledge. Looking for other easy projects you are looking to do on your C4 Corvette? Check out some other pages here.
The 1984-1987 Corvette motors are commonly referred to as the 3 wire motors. Obviously called that because the motors came with 3 wires. In 1988 a new and improved motor was created commonly called the 2 wire motors. These were a major improvement over the 3 wire motors from the early years. They are not interchangeable unless you want to mess with changing wiring.
How to remove the C4 Corvette headlight
The first thing you want to do is rotate the headlight half-way open to access the first two screws to remove the headlight cover. Its also a good idea to disconnect the batter when you start working on your C4.
Under the headlight there is a round part on the light to rotate the headlight half-way open. There are two torx screws to remove the headlight cover, one on each side. On the back side of the head light there are 2 more screws to remove and they are regular Philips screws. The headlight cover should come off easily now. Be careful not to scratch the paint on the cover or hood.
Using a 13mm ratchet and an extension you can now reach through the headlight assembly to remove the headlight motor housing. Next disconnect the wiring that is located in the headlight. You can now remove the motor using a 10mm. The bolts are arranged vertically. Then there are 4 bolts holding the headlight to the hood. You can actually take the motor out with removing this part. It just depends on what you want to do.
Its also imprortant to remove the hood strut bolt. Just be careful here. Deprending on the current quality of your struts the hood could fall. I had recently replaced mine so one was able to hold the hood up as well as the hood bracket. The bolts here are also 13mm.
Looking at the headlight motor
With the motor removed you can now pull it apart to see what is causing your issue. There are 8 different screws to remove and the motor is also held together by sealant. With the sealant you may have to actually pry the two halves apart. There are two gears, one larger and one smaller. There are also worm type gears that drive process coming from the electric motor. Typically, the issue causing your headlight not to work is the wearing down of the larger gear. This will cause the worm type gear to turn but the worn down larger gear will no longer connect.
If the larger gear is worn down a new replacement should be ordered. You can get another nylon gear or for a longer term solution its best to find an actual metal replacement. A new gear will just slip in place of the old gear for a quick repair. If they problem is the smaller gear it is a little more difficult to remove. There is a pin that needs to be removed and replaced when adding a new small gear. Just be ultra careful not to damage the plastic parts around it.
Other possible issues with the motor
This is an issue I had with my passenger side motor. It stopped working so I thought the problem was with the gears. But once I got inside I could see the gears were all OK. It appeared to me the little electric motor was bad and no longer working. Not wanting to pay for a new motor I found a refurbished one on EBay. I ordered, it was delivered and I promptly installed it. It still didn’t work. I tried to spin it manually to get it reset but nothing seemed to work. After trying to get it to work it appeared to start working backwards. It would close when I turned it on but open when I turned it off. I thought the issue was with my car, not the headlight.
I decided to check the wiring and make sure it was OK. there were no breaks or cut wires. Then I checked the light relays. One suggestion for checking your relays is to remove the one from the working headlight and use it on the nonworking one and vise-a-versa. I tried this as well but nothing changed. Another option was to try to replace the other relay that I need to look up. I replaced mine, this relay is relatively cheap, still no luck.
As with a lot of peoples C4s, I work it some and then get away for a while. This was the case with my headlight. Once I got back to and still had the same issues I tried another approach. I tried looking at the one I thought was bad and took turns plugging it in with the new one. I also tried to clean up the old one that stopped working. I discovered the electric motor was not seating correctly in its designated location. Once it was cleaned up, lots of dirt inside and I added some new grease amazingly it started working again.
Two lessons here:
- Do not spend money right away on new parts without actually looking at the part that’s not working. Remove it to see if its an easy repair that maybe only needs some cleaning up.
- Be careful when buying refurbished parts. Especially on EBay but if you do, make sure you test them out right away and respond to the seller quickly if you think there is an issue. At this point I won’t say who the seller is but I still have a passenger side headlight motor that doesn’t appear to work. I don’t want to sell a part that doesn’t work. Maybe I’ll pass it along to someone in need, letting them know it might not be working correctly.
Putting the headlight back together
Putting the new or fixed headlight back on is really just the reverse of taking it off. Just make sure it works before going through the reattachment process. Plug in the connectors and try the part before reattaching everything. Even new parts can have problems. As was my issue, make the motor is ruinning in the right direction.
I hope this write up has been helpful to those having headlight issues. In summary, the main things to take away from this post.
- 1984-1987 have the 3 wire headlight motor
- Removing the headlight motor is pretty simple to do
- Be sure to check your inoperable part first before buying something new. Sometimes it may be a simple fix or just a little cleaning and greasing to get the headlight motor working again.
- Be careful when buying used or refurbished parts. Check them completely when you received them and contact the seller as soon as possible if thehttps://www.instagram.com/reel/Chicd-jlL67/?utm_source=ig_web_copy_linkre is an issue. New parts can fail too.
Once your headlight or headlights are repaired enjoy watching them work correctly. To someone who hasn’t seen them before it can be an interesting experience and definitely one of the cool unique things about your C4 Corvette.
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