I am having trouble with my 99 Expedition! 9 out of 10 times pushing the unlock button on the keyless entry will not unlock the back door, I have to push it SEVERAL times for it to finally unlock. The same goes for the door panel unlock button, I usually have to push it several times before the back door unlocks. Sometimes the passeger side door sticks like that also. I dont know how to take the door panel off to check to see what the problem is. I would not think that the motor could be bad (which is what I was told at the dealership!) because all of the other doors unlock just fine. Any suggestions would be appreciated!

 

Try searching for broken wires. Sometime they will get in a bind and break at the point that they come out of the body and into the door/gate. Or at least it has happened to me before.

 

Power door lock accuator's are common to go out. It could be that one door. It wouldn't be the first.

My 2000 never had any problems but many people have had to replace 1 or all of them.