I recently purchased a 2003 F-250. The door locks don't work properly, the passenger side will lock the entire truck all 4 door locks actually lock. The unlock on the passenger side does not work and neither does the entire switch in the driver side. I attempted to switch the actuall switches from the driver to passenger side thinking that it could be a switch that is broken. After doing that still only the passenger side would lock and the rest of lock unlock buttons did nothing. I have checked all the fuses in my truck and actually took the door panels off today thinking I might find an obvious problem. I know the actuators are a common problem but because all the locks lock in the vehicle I was thinking it might be something else. Any guidance would be appreciated on where to look next, the ford dealership wants $100 an hour to diagnose it and they told me to expect about an hour a door until they find the problem, I don't have 400 dollars to spend on door locks so I would greatly appreciate and guidance.

 

I would start at the switch on the drivers door and check for power and ground to the switch and out to the actuators when activating. The actuators are 2 wires that change polarity depending on which way you are asking it to go.