Hey guys, about a year ago the driver side power lock switch on my '04 F150 stopped working, and I've finally gotten tired of leaning over to unlock the passenger door.

-Both doors lock/unlock using after market alarm remote
-Both doors lock/unlock using passenger door switch
-Driver side switch locks/unlocks both doors when connected on passenger side
-Passenger side switch does NOT lock/unlock doors when connected on driver side

Any ideas? I have a limited amount of electrical knowledge but anything is appreciated!

 

1) Old or new body style 2004? The circuits are different.
2) Does the switch (either one) on the the driver's door illuminate properly when the lights are on?
3) Are both the lock and unlock functions affected or only the unlock function on the driver's side?

 

If you have a New Body style 2004, did the truck come with the factory RKE ?

Checked your garage info ( same as projectSHO89 ) the truck info could be a new body style, or 2004 Heritage with the trim and cab combo.

 

1)New body style and came with factory RKE system
2)Switch does illuminate when lights are on
3)On driver's side, I can't lock OR unlock, but I can do both from passenger side

Thanks in advance!

 

That would tend to indicate that there is an open circuit between pin 3 of the switch and ground, most logically between that pin and splice S502 in the driver's door.

As a quick check, use an ohmmeter and check for continuity between pins 3 and 4 of the switch connector. Should be 0 ohms. Both should have continuity to vehicle ground. Inspect the connector for damage on pin 3.