Hello,
This is my first post on this forum. To give some info on my truck, it’s a 2010 5spd 4.0 4wd.

The issue I’m having is that when I turn my lights on, the high beam indicator comes on very dimly and neither the parking light nor headlight indicators on my switch itself light up. That’s the only oddities I can notice from the inside. Now on the outside, my left headlight works as normal but my right light is very dim. The only forum I could find with this similar issue said that he had the improper headlight bulbs in so I replaced them with the proper 9007 bulbs and the problem is still apparent. On top of the light issue, it’s also not allowing my fog lights to come on (I’m assuming from the fact that my indicator thinks the high beams are on).

As far as finding a solution, I couldn’t find much forums with this exact issue unless I’m just not the best at looking/searching. As I said, I replaced both bulbs and I’ve checked any fuses related to high beams, indicators, switches, lights. I checked they are all getting power in the fuse box and the fuses are all working as they should.

To add some further info, I have a fuse tap ran to one of the ignition powered fuses for my radar detector and that’s been on there for most of my 2 years of ownership. Now within the last few months I just wired some rear LED lights and rock lights. I also ran a fuse tap to the fuse for the door switch illumination. As far as these go Ive completely unhooked them and I am still having the issue. I also have a new Motorcraft headlight switch on order to see if that helps.

I’m out of ideas here as I’m not extremely electrically inclined so I figured I’d take to the forums as maybe this is a common issue I’ve maybe looked over or possibly someone else has ran into this.

Thanks,
Brayden

 

I vaguely remember having a similar issue on my 2003 but can't remember exactly what caused it. I seem to think it was a loose wire in the connector for the multifunction switch, but not 100% sure. I also had issues with one of my taillight sockets, but I can't remember what the issue was.

Either way, check the wiring going to the multifunction switch (push them all in to make sure none have backed out), and check the connectors at all of the lights for any corrosion.

 

When lights start acting like they are possessed I first check the ground contact for the light that is dim. If a ground is bad for a light, the current sometimes takes a wierd path to another ground for lights that are not turned on. like your brights.