Left (drivers side) headlight is VERY DIM, is this an electrical problem?

hey guys

my left headlight is very dim, I have heard from one person this may be a sign of a ground problem

any ideas/experience?

My guess would be that you've got a ground that's corroded which would be considered an electrical problem. The only thing you can do is get a multimeter and start chasing wires and clean the grounds.

Yeah, start with the grounds. I have seen it alot here lately with the trucks that have been running through the salt and crud.

Yup, check the ground for that headlight. Clean the connector also. You can make or buy an upgraded headlight wiring harness that is plug and play. It feeds the headlights a full 12v like they're supposed to get. Makes a world of difference!

If both high and low beams on that side are dim, it's the ground terminal/wiring. If only high or low is dim, it's the high or low beam terminal/wiring. Those connectors are ultra cheap and not very good quality from what I've seen, mine are heavily corroded. When I replaced my headlamp bulbs a couple nights ago (one was burnt out, the other one was intermittent) I took the liberty of retightening the terminals a little by crushing them back down to the right width so they'll actually grip the tabs on the headlamp. It definitely seems to have helped, though I really just need to get around to building a new harness.

For the hell of it switch the headlights with each other. If the bad one stays bad on the other side you have a bad light. If not check and clean your grounds. Or better yet make a new harness to give them the full 12v they deserve.

Check the main front clip wiring connection in the left front fender area. It's by the airbox/fender/core support area.

Check for voltage directly across the headlight plug. It should be VERY close to what you get across the battery terminals. If not, check from positive in the plug to negative at the negative battery terminal. If that checks good, your ground is bad.

magimerlin said:

For the hell of it switch the headlights with each other. If the bad one stays bad on the other side you have a bad light. If not check and clean your grounds. Or better yet make a new harness to give them the full 12v they deserve.

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x2. i would make sure its not just the light itself first