Door Lock Issue

[Heavymech64]

Seeing that I have not come across a similar problem in the forums on the 3rd gen expedition. I wanted to post it here and get any ideas from the members. Last week my driver side door lock quite working, then worked once or twice randomly then died. I immediately thought actuator. Bought OEM and replaced. Still nothing. Tested power to the switch. 10V. OK. Tested continuity of the switch between the points. OK. Tested power at the actuator. Nothing. Checked it back to the main connector block in the door. Nothing. Checked the harness at the door hinge. No visible issues. After many hours of frustration with no resources to look at, I traced the wiring to the fuse box in the passenger side footwell. The book labels a fuse for lock/unlock relay. Checked the fuse. OK. Pulled the fuse and the locks still seem to operate... not sure whats going on here. Put the fuse back and next locate these refrenced relays. Audible checks lead me back to that fuse box. Relays are clicking inside. Pulled it and split the box. Nothing but circuit boards inside... now if I was an electronics guru I would pull it apart further and solder in a new relay. My only guess at this point is the contacts for the Driver side door circuit are fried and I now need to replace the whole fuse box assembly. I will price one out through Ford and also see if a wrecker has a 3rd gen that may work. Any further suggestions?
2017 Ford Expedition Limited EL

 

[Robbin Adams]

I have the same problem and I replaced the actuator and it did not fix it. If you replace the whole fuse box assembly will that require some programming to make it work?

 

[Plati]

Probably a dumb question ... but you get same results from all three ways to actuate electronic door lock? key fob, switch on door armrest, keypad on door exterior?

and all other doors operate normally with those methods?

and physical key works?

10V sounds odd, although I don't know circuit.
should be same as battery voltage shouldn't it?

 

[Yupster Dog]

next locate these refrenced relays. Audible checks lead me back to that fuse box. Relays are clicking inside. Pulled it and split the box. Nothing but circuit boards inside... now if I was an electronics guru I would pull it apart further and solder in a new relay.

Did you try pulling the relay next to it and trying that? Even though it is clicking it still could be bad.

 

[Heavymech64]

Yupster Dog, So this new style does all the actuating through the fuse box AKA the body control module. No physical relay to replace or switch around like what is found on the older style expi's. I was unable to locate a good schematic to further troubleshoot and took it into Ford. I guess they found a broken wire going from the body control module to that actuator. Somewhere up in the firewall, guess it took some ripping and tearing apart of panels etc to get to!! So for now issues resolved.

And for a response to Mr.Sticker I don't believe in dumb questions, its actually the right one. Start with the simple checks. Short answer is yes, I did try all functions you mentioned with the same result. Always a good reminder to start with simple checks.

And Robin Adams. From what ford explained to me the Fuse Box AKA body control module has to be replaced as a unit and even programmed to your vehicle parameters to function properly.

 

[Yupster Dog]

Yupster Dog, So this new style does all the actuating through the fuse box AKA the body control module.

Did not realize it went thru the BCM.
ok try this,
https://www.expeditionforum.com/threads/power-locks-not-working-from-either-door.43857/#post-397381