In Cabin Bright & Reverse controls for Aux LED's
 

Hey everyone! I'm getting a 32" LED lightbar for my 2010 F150 Lariat for Christmas and I'm trying to figure out the best way to wire it up. I'm planning on using an ON/OFF/ON switch to flip between switched power on relay 37 inside the cabin and the bright light signal to control a relay. This allows me to use it anytime the ig. switch is ON, or in conjunction with my high-beams.

Is there someplace in the cabin, maybe under the sill plate or driver side kick plate, where I can use a posi-tap to tap into a bright-light control wire? I also have 2 backup lights that I'm planning on hooking up the same way with a reverse light wire in the cabin (think it was BK/PK).

Also, if you have any tips on mounting the light bar in the grill, let me know! :) I'm planning on putting it somewhere so it shines through that top slot above the blue oval.

https://cimg1.ibsrv.net/gimg/www.f15...6e77a3afc1.jpg

Not sure why it was sideways in the OP...

I wired my aux lights to high beams only. So I snagged the wire at the pass side light and installed the relay there by the battery. Also powered the lights from the battery thru a fuse. If you do that then you only need to run a wire to the cab for your switch. You will need a diode between your hot wire inside and the switch so you don't backfeed.
For the backup lights, I wired them to my 7 pin trailer harness and put a switch in the bed. Easy and short wire runs.
FYI on my 2011 the headlights get power from the Body Control Module not the headlight switch. Likewise the BCM raises a BU-WH wire to 12V for reverse. That wire runs several places like the mirror (to turn on the camera display) and the lights themselves and the Battery Junction Box under the hood to turn on the trailer tow relay which sends 12V to the trailer harness thru a Gy-Bn wire.

I'm not really following the part about the diode. If you're only using the tap off the high beams into a switch and then to 85 on the relay, how would that backfeed?

On the diagrams I found terminal 85 is the relay coil ground.

If the High beam +12V from the truck is used to power the relay coil and you also power the relay coil from your switch in the cab, then when you turn your switch on, it will feed 12V to the high beams.
The diode goes between the high beam +12V (truck) and the relay coil. It will block the 12V from your switch.

I'm not sure it really matters, but you are correct in that the schematics say 85 is relay trigger ground. But I also think we are talking about two different wiring schemes.

This is what I'm planning on doing. It sounds like you're talking about wiring switched power and the high beams both directly to pin 86, in which case you definitely would need a diode. But I'm talking about wiring those two separate legs of an OFF/ON/OFF switch. Essentially a SPDT, but with middle position that's "OFF".

https://cimg2.ibsrv.net/gimg/www.f15...e20a0e0b9e.jpg

That looks great. You can try the colors mentioned above but Ford has been known to change wiring year to year.