Very recently the low beams on my 2006 F-150 Lariat stopped working. I do have some after market LED's in place. However, I removed them (they are plug and play) and put the OEM headlights back in. Same problem. I have checked both low beam fuses (#23 and #25) as well as fuse #40. All of them are good to go. What are the chances that the MFS is the issue? Any help is greatly appreciated!

 

Check the relays.

 

I am having trouble finding a good diagram of which relays are for the low beams and where they are located. My search online seems like I am searching through a haystack to find the needle.

 

It's in your Owners Manual.

If you lost your OM, get a copy here:

https://owner.ford.com/tools/account...r-manuals.html

I recommend printing it out and keeping it inside the truck in case of breakdown.

Check pg 241 of your OM... says Relay 03.

There's a picture of your fuse box right in there.

Good luck.

 

There are no relays in the base lighting system for the low beams, it's all done with switches.

Very high.

 

Thanks guys for the input. I do still have the OEM manual and couldn't find a relay that would be helpful. There was another thread on here regarding this same issue but I can't seem to locate it. Seems like everything kept coming back to the MFS.

 

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