Power Windows/Locks problem

[Thomas Su]

I have two problems I'm currently trying to figure out with my Sport Trac. It is a 2004 currently sitting at 136k miles.



My power lock switches in the car will lock, but will not unlock. This is the same for the switch on the passenger side also. Unlocking works fine with the key FOB, and the number pad on the driver's door.



The other problem is I can roll up + down my passenger-side rear window from the driver's switch, but I can ONLY roll down using the switch on the passenger-side rear window. In order to roll it up, I have to use the driver's controls. I assume the motor is good but the connection is bad somewhere in that passenger-rear door.



Any hints on where to start checking or what could be wrong? Thanks.

 

[Rick Kent]

Check the wires coming out of the door into the truck. You have to get into the bundle but many of us have found broken wires over time from opening and closing the door over the years. Splice any broken wires back together.

 

[Taylor Corn]

Is your door lock problem with all 4 or just up front?

 

[Thomas Su]

@Bigt1989: Only the switch is not working properly, it locks but cannot unlock. All the doors work fine with the key FOB.



@rangers484: I checked today and spent all evening soldering the power unlock wire (pink/green I believe) together. It was not completely cut, but the insulation was tearing, so I spliced it anyways. BUT, it did not fix the problem.



When I put the power UNLOCK wire to my multimeter, it reads 0.11 V. I'm thinking it should be grounded out to 0 V like the power LOCK wire. So I think I have a bad ground somewhere for that wire, I'm just not sure where to look.

 

[Taylor Corn]

Okay it still sounds a little like the issue I had where the actuator rivet was failing at the door, allowing it to become loose, and not throw the lock as far as needed.



Basically as a result of the auto lock function the front doors started to not want to unlock with fob or button, starting infrequently at first and becoming a recurrence each time. Locking was never a problem.



Had to replace the rivets with bolts to fix. I originally thought it was electrical but eventually discovered otherwise, reason for my comments.

 

[Thomas Su]

My power locks work just fine with the key FOB. So I don't think it's a mechanical issue. The buttons in the car just won't unlock when I press it.



I'm thinking it could be a corroded relay connection.