Thread: Door unlocks but doesn't lock

I'm thinking it's the actuator but would like a second opinion.

Both doors unlock through all methods, fob, switch, etc, but the driver's will only lock using the manual lever. It won't lock through the switch, remote, or coming out of park. I tested the switch on a meter and it appears ok, and swapped it with the other side. I do see a pulse of power at the actuator when trying to unlock. All signs seem to point there, though it does seem a little unusual it fails only one way, I assume there's a motor or similar in their that goes one way to lock and the other to unlock. Maybe some teeth went.

Well, got my new actuator and have the same issue. I've currently got the door lock/actuator/rods out and doing some bench testing. I can see putting pulses into it does move the lock rod in and out, and the old actuator does respond to lock/unlock pulses as well so it was probably ok. At a bit of a loss what to do next... will have to put it back together in the morning and see if the rod still moves when not on the manual lock switch. The manual lock switch does work, but maybe there's an issue with it sticking/stiff and not enough torque electrically.

Also, side note - where the actuator connects to the door lock plate there is a small partial gear (like 1/4 circle), not sure what it's for - it's there a best way these should be mated? Can see it here:

http://shop.advanceautoparts.com/wcs...7_pri_larg.jpg

It can go to the far left or right and only have a tooth or two exposed

I just took another quick look at the manual lock switch and it's freely moving and I don't think that's the cause - for some reason I thought there was a spring or something. Completely out of ideas now

An update ... re-installed it, didn't work but as expected since I believe the old actuator was ok (used new one) and all I really did was lubricate it. One bit of new info - I was able to make my own connector so I could power the actuator directly via a 12v power supply will in the door, and the door does lock when pulsed via the external source. I do see a pulse though on the factory connector, though it's hard to read on a meter since it's so quick. I wish when I was using my custom connector I would have tried swapping wires and see if the unlock signal I know works would lock the door and vice versa. Probably will leave it for a while.

One a side note for future reference it did seem the gear position matters, it's used by the door ajar sensor and does open/short based on the position. I used this image from a youtube video setting the lock and gears in the same position and verified it worked on a meter moving the door latch manually

Final update for future reference, I've gotten it fixed. Even though I was showing an unlock pulse at the actuator on a meter and test light, something was up with wiring - perhaps enough amperage couldn't get through? I connected by extra lock actuator directly to the BCM under the dash (A/Tan & C/Gray) and it worked, so I ran two new wires from the BCM through the door to the actuator and used taps on each end so I still had the factory wiring connected.