Hi folks. Hoping someone can help me out with an issue. I have an '11 FX4 Screw Ecoboost. Randonly two weeks ago, My low beam went on the passenger side. Figured it was just the bulp, so pulled out the old (wasn't blown) and put in a new one, same problem. So I squeezed my 275lb frame into the passenger foot well and switch out the fuse for the passenger low beam, and still the same issue. High beams work fine. Any ideas where I should start to trouble shoot this??

 

No one?

 

You really need a wiring diagram to work on this. You could compare wire colors and take voltage measurements at the bulb socket on the left and right side to narrow down the problem. I would guess the wiring harness splits somewhere or the right side is fed from the harness at the left socket. Once you figure out what wire has the problem, you could begin to ohm out the wires as you follow the harness back to the split point.

 

Hi.

It's purty simple:

https://www.f150online.com/forums/me...ead-lamps.html

( Courtesy Steve fer the diagram )

good luck!
MGD

 

Thanks guys. Once this dang snow storm passes, I'll see what I can figure out....

 

Hey, send me a PM with your email address. I will send you a copy of the section from the factory service manual. Ya, the wiring diagram is useful but this will give you the pin test details too.