I recently started having a problem with my driver's side headlight. It was popping up very slowly or sometimes not at all. If it did pop up, the light was significantly dimmer than the other side. I have seen several posts by people trying to fix this exact problem. However, I couldn't find anyone who specified exactly which connector definitely causes this problem. Well at least not the connector that was bad in my case.

After a couple hours of tracing and replacing grounds, I found the culprit... JC-01. You can find this one on pages Y-2 and Y-3 of the Body Electric Manual. Since I have a Greddy FMIC, it was really tough to find. It was sandwiched between the frame and the top-back of the FMIC. I cut the old corroded connector off and soldered a new ground lug on. I then sanded off a patch of paint nearby and bolted it to the frame (you probably have several pre-tapped holes near the hood latch that would work great). The headlight is now working perfectly! While I was at it, I also replaced JC-02 which provides ground for the passenger side headlight among other things.

I strongly recommend checking/replacing your ground connectors when you have your car apart. There are at least 16 of these according to the FSM. I know others have found similar improvements when replacing the fuel pump ground. Why not make your interior lights a little brighter next time you have the seats out

 

Good stuff! Crappy grounds can cause all kinds of bad problems. Glad it's a relatively easy fix!

Dale