Hey all, hoping to get an assist. I have a 2009 F150 Platinum. Rear driver's side door power locks no longer work, but ONLY when the door is closed. When the door is ajar, the door lock works as expected. This is true from the fob, and driver/passenger side front switches. I figured the actuator had gone bad, so I replaced it. New actuator is behaving identical to the old actuator. I have the setting configured to unlock all doors with fob unlock, and all other doors behave as expected. So it can't be a fuse issue. And in terms of electrical, the wiring must all be correct because it works when the door is ajar. If I close the door while locked, it stays locked. If I close the door while unlocked, it stays unlocked. But while ajar I can lock/unlock all day. This just started happening maybe a month ago. Any ideas?

 

I had a similar issue with my 2012 fx2. What I ended up doing was taking the plug that goes onto the actuator off, cleaning it and the contact point on the actuator with contact cleaner and additionaly puting a dab of dielectric grease on the plug. My theory is that when the door is shut it is jiggling a contact somewhere loose, it could also be due to moisture which can cause corrosion. That was part of my problem as my drain holes on my door were clogged with mud due to the previous owner having a long dirt driveway. Good luck hope this helps.

 

Sounds like damaged wires in the door jam area to me. Bending them one way when open, another when closed, makes or breaks contact. Also, it's a common issue.