I have an 02 Expedition which, obviously, has the Child Safety Locks. My problem is that when the lock on the passenger side is NOT locked, it becomes locked on its own. I have investigated and found that whenever the door handle on the inside is pulled 4 or 5 times the lock works is way from "unlocked" to "locked" all by itself. Then, my son can't get out. It is very frustrating. I tried the simple solution of duct taping the little lock to the unlocked position.....it didn't work. Any other suggestions that aren't going to cost me a ton of money?

 

Sounds like the lock actuator is going bad and sticking. The part is around $40.00 and takes about an hour for a nOOb to change, but you will need a rivet gun.

 

I hope someone answers this I have the same vehicle with the same problem. I never investigated the cause. It only happens on the left passenger door.

 

First time at this forum. Actually looking for an answer to a different problem, but my 2001 is doing the same thing with the child locks. I thought my younger daughter kept playing with the switch when the door was open! this site is cool!