2000 4Runner-cannot manually unlock door

My transponder key will not manually unlock my driver's door. I can manually lock it and the remote works properly. I can manually lock and unlock the passenger door and rear gate. It had this same problem when I bought it new on the lot and when I had them look up the records, all they could tell me was "an ECU had to be replaced. Any ideas what the problems might be and/or what parts I may need? The only thing I've been able to find on the net thus far is a lock actuator. How hard would it be for a total novice to replace this? Thanks.

Bump--Hoping for some help!

Welcome to the AF!

You have to remove the door inner panel. There are torx screws holding the lock in place - these need to be held in place with adhesive TB324 when replaced.

If there is such a part as the lock actuator, it is inside the lock mechanism and not described in the repair manual.

Can you lock and unlock the driver door with the lock switch on the driver door arm rest? If not, then it is probably the lock. If you can, then there is an actuation circuit that is not functioning.

Yes, I forgot to mention that the door panel switch does work normally. This happened right after I had this door repainted. I don't know if they normally remove the door panel to repaint it, but I wonder if they could have knocked something loose or if it is purely coincidental.

I can't figure it, but here are some portions of the manual that relate to your problem. The only smart part of the system is the body ECU.

http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/DoorLock1.jpg
http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/DoorLock3.jpg
http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/DoorLock2.jpg
http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/Door1.jpg
http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/Door2.jpg
http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/Door3.jpg
http://i16.photobucket.com/albums/b8/rogersb/4RunDoorLock/Door4.jpg