So my driver's side headlight is not out, but dim. It used to work sometimes, but now it is always dim. I don't know what the problem is, I was told at some point that I need some type of new wiring harness or something, no clue. Who should I go to for this?

 

What year is the car? Are your headlights OEM ones? I know if you put brighter bulbs in the headlights, they can overheat the connector and melt it were the harness plus into the back of the headlight. You can splice a new connector into the existing wiring harness and see if that works.

 

try some contact cleaner thay sell it at radio shack

 

Yeah, I melted three sets of headlight ballasts with non-oem bulbs. My lights got dimmer as the plastic melted, and eventually didn't make a connection at all. It was oem bulbs from that point on.