I have a 1999 3rd Gen 4Runner SR5.

The driver side door lock is acting up. Keyless entry works fine; door locks unlocks, the main key works fine, door locks unlocks. So it’s not the door actuator. The issue seems to be the driver’s side door control panel switch, it will unlock the door but is acting up when I try to lock the door, it only works intermittently.

So my thoughts are; there’s a short in the wiring somewhere on the locking side, or the actuator under the button for the driver’s side door control panel is the problem.

I removed the drivers side control panel, took it apart, was surprised there was no corrosion, considering the water that comes through the windows when it rains because of the trucks design, I cleaned the entire unit, contacts etc. but the problem persists, any thoughts on how to test the signal from it?

Been a while since I've asked for advice, there seems to be a tendency to get replies completely sidetracked off the issue.

Is there any reason not to consider replacing the switch? Seems more likely than an intermittent open in the wiring. I've never had that switch apart to see if the part that moves the contacts could wear down to the point of being too short. Jumping the switch contacts would be the most definitive test as to which direction the problem was in. Sorry if I misunderstood your post.

Along with the switch, it could be the wiring in between the door and body.

-Charlie

Thats mostly where it gets me.. Even more noticeable when raining or really damp too.. :-)