OK this is driving me bonkers. I bought a used 1998 F150 4.2 with the 5 speed manual. When I bought it the windows did not roll up and down. After messing with the switches and testing the window motors I determined one motor was froze up and one of the switch contacts was loose. In the process of fixing those the door locks quit unlocking (actually I don't remember if they worked or not I was focused on the windows LOL). They will lock fine from either side but not unlock. Looking at the wiring diagram I tested the voltages from ground to the lock and unlock side of the switch. Lock is pink/black and unlock is pink/orange (on the passenger side, colors are diff on drivers). When I lock the doors I get 12V on the pink/black. When I unlock I get 12V on the pink/orange. Whats strange is when I lock I also get 12V on pink/orange but unlocking does NOT get 12V on the pink/black only on the pink/orange. If I unplug the actuators I get 12V on the lock side (when I lock) and 12V on unlock side (when unlocking) but not the weird 12V on both when it locks. I've tested the switches and they show "closed" only on the lock and unlock neither is closed on both. Would a bad actuator cause this weirdness? I would think you should only see voltage on one side when you lock not both? Am I missing something here? If I apply voltage to lock with a jumper it locks, if I do the same on unlock it blows the #3 (I think) fuse under the hood. The one for the all lock/unlock if I recall.
Truck does not have factory alarm and there are no relays under the oval insert on the dashboard. Grounds all look great no corrosion. I checked the connectors in the the kick panels, doesn't look like any moisture on the GEM/fuse block etc... No broken wires that I can find between door and body. Everything looks fine.
I guess I'll go take out the actuators and bench test them.
Thanks for any help!

 

I would remove the drivers switch and disassemble it carefully if possible. The contacts inside may have a greasy black buildup on the points not allowing the proper currant flow. You might want to do the same to the passenger side switch. When I disassemble switches, I try to warm the plastic with a heat gun or hair dryer first so as not to crack the plastic when prying the lock tabs away.