I having some weird electrical issue with my 2010 F150, 4.6l, regular cab. Intermittently, my A/C blower and turn signals stop working. The kicker is, when they are not working, the truck cannot be shifted from park into drive. I've searched the forums for hours, I see that the previous gen has an issue with the grounds behind the kick panels rusting out. I checked these grounds, no corrosion, cleaned them up, torqued them down, and the problem remains. I installed a new battery and battery cable. I'm going through searching for grounds, cleaning them as I go, but still have not found anything that appears bad.

The only thing that I have noticed today is that my accelerator pedal/assembly feels like it has a little play, and I wiggled it around and now the problem is much less persistent. I bought a Haynes manual online, hoping for some of those sweet drawings that show ground locations, and I guess those aren't as good as I remember them being, because... I can't find any helpful diagrams or pictures in there. I think even if I knew which ground these things had in common that would help.

Anyone seen this before? It's driving me crazy.

 

Not sure about Haynes branded, but Ford's manuals come in 3 parts. The wiring diagram is a separate book.

There are 3 grounds up under the dash and then 1 behind each kick panel. Probably one or two on the back wall or corner, and one on the floor. G202 covers most of the functions you are dealing with, I think. This is 2012, but I think it's the same.

 

Check all the electrical connectors on and around the BCM (Body Control Module) which is behind the passenger side kick panel. Seems like one may be loose, not clicked in place. Also may be a loose fuse in the BCM,

 

Figured I'd follow up on this just in case anyone else ever stumbles on it. This has still been an ongoing issue for me. The problem has been less intermittent, and more just not working. I finally checked and cleaned all my grounds including G202. Today I removed the BCM, tested all the fuses, and reinstalled. Everything worked for about 30 seconds, first time it's worked in over a week. I've found that if I remove and reseat the large connector everything will work for a moment. I didn't see any pushed in pins on the BCM, the connector feels like it seats well. Wiggling it doesn't affect operation. I'm thinking it's either the connector or the BCM.

 

Which connector? The one with a locking arm? It can be trickier than expected to lock in.

 

1.Check the ground straps outside of the truck, below the doors. They attach from the frame to the body. Remove them and use a wire wheel on a drill to clean them. 2. Maintain a full charge on the battery. 3.Check for rodent damage to wiring harnesses, especially the ones that connects to the BCM which seems to make the problem resolve itself for a short time after you touch it. 4.I would use Forscan to see if any codes or communication issues are occurring. Before replacing anything troubleshoot as much as possible. Parts can get expensive.