This question got lost in my intro/build thread and after searching for a few days on this topic I felt it warranted its own thread… for some reason my driver’s side lock/unlock button will not lock the door. It unlocks but does nothing when I press it to lock it? I Played with the lock switch, it's not the switch. I swapped it to the passenger side... it worked. Put the pass side switch in the driver side, no worky... now I gotta figure out why..? Anybody know the color coding on the wires or have a wiring diagram?? The search turned up tons of actuator issues. I don’t believe it has anything to do with the actuators because all the other switches work. Is there a relay or something in the drivers door I need to check?

Wires to the switch:

 

Have you checked to see if you are getting power to the wire when the lock button is pressed?

 

it unlocks it so i assume its getting power. I gotta get a wiring diagram and start checking points. I did check the plug on the jamb, everything looked tight there.

 

I've never had to work on them, but I wonder if one wire controls unlock and one controls lock. Since you know the passenger's side works you could hit it with a test light and see if lock/unlock is ran off the same wire.

 

yeah, thats probably what I'll have to do... but w/o a diagram it's like poking around in the dark.

 

With only 4 wires it shouldn't take long though. Test each one without pressing a button, write down whether it had power or not, test while pressing unlock and mark it down then repeat while pressing lock. You'll know if they are ran off separate wires and which one controls which so you know what to check on the drivers side.

 

I'm confused. You say it can't be an actuator because all of the others work. It's got power because it works sometimes.
Are you sure it isn't the old thermistor issue as noted in probably one of the longest threads here at FTE?
I'd go back and re-read that thread as that's the most common issue as you describe with a fairly simple fix.

https://www.ford-trucks.com/forums/4...cks-fixed.html

 

Four wires that runs a switch that does two things. I would say block is ground. One is always hot. Other two run the power to lock or unlock. See if one always has power. Than try to jumper to the other wires to make it lock/unlock. If one unlocks and other does nothing you found your culprit wire.

 

r2millers - The lock works. It locks and unlocks (All 4 doors) fine from any other switch except the one on the drivers door... Which only works to unlock it. The key fob - Locks and unlocks all four doors. Pass side door switch - Locks and unlocks all four doors. Putting it in drive and going over 5mph - Locks all four doors . Putting it in park - unlocks all four doors...

I spend the majority of the last 3 days reading through that particular thread... not to say I didnt miss something... But that was for fixing the actuators

The Driver door switch will not lock the Doors - It only will unlock them. all other switches work.

Theory one: Because this was a fleet truck and has a my key active, could it have been set to function like this? Perhaps the guy who's truck this was kept hitting the button?? Thus far I have found no cut wires or anything but I will look further.

 

Use a multimeter on one of the working doors to figure out which wires are hot, then jumper them one at a time to the ground wire in the plug, this should let you figure out what each wire is for.

After you do that go to the non working door and see if the hots are the same, if they aren't trace the wire that isn't hot at the plug it is likely broken some where, probably in the plug, that looks a little corroded.

 

Thank you! great pointer. They are not corroded, just dusty...which may contribute to a bad connection as well....


Going camping for the weekend, I'll update with the results next week.... (if I get to messin wit it!!!)

 

This is basically what I suggested also. I would bet your paycheck it is one of the wires. But you have to find out which one. Once you do you can track that wire to where it is loosing power.

 

what year is it, model, ect. Or did I miss something?

 

Sorry- 2012 xl

 

I had a 08 F150 with a similar problem but was the window control switch that was intermittent . I disassembled the switch pack ( not to hard to do) and found carbon build up between the contacts . I used rubbing alcohol and fine emory cloth to clean , then applied a small dab of dielectric grease to the contact points .
No more problems .