I replaced the door on my 1994 F350 with a door from a 97 F-Series. The wiring harness on the 1994 had two red color wires for the power lock, the wires coming from the power locking motor on the 97 has four wires. In addition to the two red wires, there is a green and black wire. Both doors had the wires cut by the previous owners.

What are these two extra wires for? When I spliced together the two red wires together, the door lock would grind, kind of like when two plastic gears are worn out and not engaging all of the way, and would not move the lock.

Any ideas how to wire and fix this? What parts do I need?

 

1994 Power Door Locks:






1997 F250HD/350 Power Door Locks: