Driver Door Lock Issue

nixhex_is_on · December 16, 2014

So I recently replaced the driver side mirror on my 2007 GMC Sierra. Ever since that day I have had issues with my driver door lock. It stopped opening from the inside and outside. I removed the door panel and got it working. Awhile later it stopped working again. Today I dug a little deeper in my troubleshooting. I removed the panel and got it working yet again. I put it in drive to see if the auto-lock was causing it, pressed the lock/unlock on the door switches, manually pushed and pulled the lock to see if any of those were causing my issues. Apparently they were not because everything was working fine. I picked up my tools and begun to walk away from my truck. I pressed lock on the key fob and the doors locked. I pressed unlock and the lock moves up as if it unlock but once again my door won't open. So my best guess is something about the way it locks when using the key fob is rendering the lock useless. I was hoping for any advice before I go and spend an arm and a leg at the dealership for the repairs. Could it be the actuator? Or maybe something else I'm over looking?

Doug_Scott · December 16, 2014

You don't say what generation or trim level the truck is. I am talking about the 2007 style that looks like a 2010 Sierra. Also I am referring to a non-SLT trim level.

Take the panel back off again, and verify that the lock rod is connected at latch assembly end, and is not just hanging there. Also make sure that when out put the lock button part back onto the rod assembly at the top of the door panel is phased correctly. By this mean that you are not trying to put the button back on with the rod not in the completely unlocked position.

Actuator may be the issue, if it is not pulling/pushing rod far enough, but, unless someone touched it, it should work the same way it did before the first time the panel came off.

Lock assembly, while a pretty complicated design, it actually quite simple to trouble shoot. Rods have to be securely attached at both ends, and must be installed in the correct orientation(as in not backwards or upside down). Some of the attachment points have a provision for adjusting it. Start at the ends that you actually touched first. Little chance that it will be failing at an area that was not touched at all. But, never know, sometimes people that do not know how to do something will experiment with different procedures. Not an issue if they reverse whatever change was made before trying something else. But if they don't, chance of it failing will go up exponentially, and be a bitch to fix due to having to undo what was done first. Something I learned many years ago, "one change at thing/setting at a time, and undo if it does not work before trying something else".