One headlight dim

[Vsantoro]

Hi everyone hoping for some assistance.
62 corvair convertible.

My drivers side headlight had been dim since I got it. Today I decided to get all new headlights. I hooked up the passenger side and drivers side low beam and same problem driver side is very low.
Cleaned all wiring , applied grease , same issue.
I haven’t tested voltage yet, I’m done for tonight.

Any ideas why this could happen ?

[Lane66Monza]

Pull the bezel and attach a jumper wire (12 ga) from the bulb cup mount to the bumper or other good grounding point. There is a grounding wire from the dual bulb cup mount to the bucket. If it brightens up, fix both ends of the ground wire by cleaning. You may have to loosen and restall bucket screws to get a grounding connection since the bucketis sealed in. An ohm meter comes in handy to check ohms from a bare spot where ground wire mounts to the clean body metal away from the bucket.

If not, pull light from cup and jumper a wires to the battery and ground to see if beam increases intensity. If not, get a replacement . Use this diagram for use of each terminal Confirm your car is wired this way. If not, use your car's wiring as a guide. This is a generic diagram by AAW.

[66vairguy]

Al's comment about a bad ground is most likely the problem.

The headlamps are glass, so each headlamp must have one ground terminal. The headlight socket has one ground terminal and the wire goes to the headlight mounting assembly that is bolted to the car bucket (which is usually bolted to the car). It is a multi-contact ground path, and not the best, especially after years of corrosion. Bottom line --- any amperage that goes to the headlight filament must return to body ground (that the battery ground is connected to). Even when new the ground wire from the headlight connector was JUST adequate.

I add a new ground wire (and terminal) to the headlight socket and run a ground wire back into the trunk and screw it to a good clean metal area. If you run a separate ground wire from each bulb, then use a 16GA wire, but if you combine bulb grounds on each side and run one wire into the trunk, the use a 14GA wire. Sometimes I get a noticeable improvement in headlight brightness by only improving the grounds.

Good luck.

[PrismSky]

It could be a grounding issue on the driver’s side headlight. Even if the wires look clean, a bad ground can cause dim lights. Check the ground connection specifically on that side—make sure it's solid and not corroded. If that’s fine, testing the voltage tomorrow should help pinpoint the issue.

[Wittsend]

... Even when new the ground wire from the headlight connector was JUST adequate. - I add a new ground wire (and terminal) to the headlight socket and run a ground wire back into the trunk and screw it to a good clean metal area. ...

Excellent advice. And I go even further. I solder a ground wire to the housing/socket and solder the other end to an elevated pinch weld with a BIG Ole solder iron. The likelihood I will ever need to detach the housing/socket from the car is FAR less than I would have grounding issues if left as it was manufactured. And if needed all it takes is the snip of a wire cutter to remove.

[Lane66Monza]

On my coupe, I have started assembling the lights. I have added another ground wire outside the bucket, from the bucket to the sub-frame right below it. Clean and bright meatl, install the new wire, torque and paint over it. The ground wire inside the bucket is treated same way. Now, the ground path doesn't use the bucket screws for grounding.

[Vsantoro]

Thank you everyone. Does anyone have a pic of the new wire they attached for ground to the headlight bucket ? Do you mean to the wire harness on the back of the bulb or the actual steel bucket the lamp sits in ?

[Vsantoro]

Never mind my last post , you guys hit it in the head thank you. I put on a new ground wire to the ground connection on back of bulb and it’s perfect now. Thanks again .

[66vairguy]

Never mind my last post , you guys hit it in the head thank you. I put on a new ground wire to the ground connection on back of bulb and it’s perfect now. Thanks again .

Thanks for reporting back so others can learn.

I've "brightened up" a number of Corvair headlights by just adding a better ground.

[American Mel]

It could be a grounding issue on the driver’s side headlight. Even if the wires look clean, a bad ground can cause dim lights. Check the ground connection specifically on that side—make sure it's solid and not corroded. If that’s fine, testing the voltage tomorrow should help pinpoint the issue.

the bots are getting better

[66vairguy]

the bots are getting better

It is just a matter of time before a car forum is run by A.I. One good thing it will get rid of the "snarky" comments.

[joelsplace]

All they can do now is regurgitate previous answers in a different way. I've found that most of the AI search engine answers are wrong. So far. It is really aggrivating to me because often the answers sound like they could be right.

[Vsantoro]

Wow I didn’t know that was a bot. Crazy.
What’s the benefit of bots answering questions on here ? Is there people creating accounts then setting up some bot with the credentials ?

[monzadon]

i am a retired auto body repairman and i have found that usually if you have dim lights it is a ground problem

[JayPaul]

Not to go too far afield, but in other less refined forums I have been acused of being a bot. Quickly realized that it is close to impossible to change a person's opinion on that sort of thing once comment is made.
JayPaul

[66vairguy]

Not to go too far afield, but in other less refined forums I have been acused of being a bot. Quickly realized that it is close to impossible to change a person's opinion on that sort of thing once comment is made.
JayPaul

Yes some folks don't like to be confused by facts. Attempting to inform them just makes them mad. As a wise businessman I knew would say: "Don't try to teach a pig to whistle because they cannot. It wastes your time and irritates the PIG!


Once you learn how irrational/illogical folks are you will understand how economics work. P.T. Barnum was correct.