Helping a friend who had an accident in his 2014 F150 XLT Screw. Both headlight housings broke mounts but HID's still work. Not turning in on insurance.
Struggling to find housings, Carparts.com has the driver's side for $274 and passenger side for $290 minus the bulb or ballast or $564 total.
The plug is a 4 pin plug whereas the halogen plugs are 3 pin and they're not interchangeable. It seems every aftermarket HID is a conversion off the 3 pin.
Carparts.com has a pair of halogen housings with bulbs and CAPA certified for $171. Trying to keep costs low, can't find used HID ocally and frankly, on a
10 year old truck, they're likely hazed or cracked. He doesn't care about looks or halo rings or any of that, just ones that work. I know HID is better than halogen.
I can get cheaper halogen on Amazon but I'm not sure if the reflector pattern is as good.

My thought was to go to the salvage yard and cut off some halogen pigtails and cut the 4 pin plugs off and wire them in, assuming the colors match. I guess
I could leave the 4 prong plugs and splice the 3 pin in, but with 179k on the truck, he's going to drive it until it isn't worth driving. (He had a Suburban with 420k
on it before this truck.) I have no idea if all the other plugs are interchangeable going from an HID housing to a halogen housing, or if the sockets are the same.
Or is there a 4 pin female to 3 pin male harness?

 

HID are about $500 each brand new. I assume that's higher than wanted? I recently replaced one HID with used and it cost me about $400, although that did come with a bulb and ballast. Here's the difference in wiring, I believe you would also need to reprogram the BCM with forscan, but not sure on that:

 

HID wiring

Halogen wiring

Note that the left and right HID headlights have separate fuses, which is not needed with Halogen headlights. The wire for these two circuits are the largest of the 4 wires on each headlight. As they're not needed, cut them, and remove the two 20A fuses.
Auto parts stores stock 'H7 headlight pigtails' for about $10 each. Theyre generic, but fit fine. The wire colors wont match though. The center wire on the 3-pin plug is ground. So, identify the ground wire from the 4-pin plug, pin 4, snip it & solder to the pin 2 wire on the 3-pin plug.
Identify the high beam wire on the 4-pin plug, pin 3. Snip it, and solder to the 3-pin plug wire, pin 3. Identify the ĺow beam wire connected to the 4-pin wire pin 1, solder to the three-pin wire pin 1.
That's it, electrically.
Make sure the solder connections are insulated with heat shrink, then spiral-wrap the extended wiring harness with electrical tape. You're now ready to use halogen H7 bulb headlights, optionally with PNP LED headlight bulbs, or after-market HID headlights.

Note that on high beam halogen, both filaments (LEDs) are lit, but on low beam, only the low-beam filament (LEDs) are lit.

I just did this today. Did not have to change anything with Forscan. It worked fine, didn't throw any codes.
The wire on pin1 of the 4 pin plug goes to pin1 on the 3 pin plug. Likewise, the wire on pin 3 of the 4 pin plug goes to pin 3 on the 3 pin plug. Pin 2 changes from 12v hot to ground, when changing from HID to halogen, though.

The outputs can detect the change from 12v to ground on the common pin, and automatically adjust the output from current sink to current source, with no changes needed in software.
The chart below shows where the wire on the 4-HID connector is moved to on the 3-Pin halogen connector.