Door locks by itself... remedy.

[Machiner 55]

I believe I have one, and possibly the , solution to the problem with our doors (mostly the drivers door)
where the door lock itself when the door is closed. This happen more frequently during the
colder months when thing seem to get sluggy and stiffen.

There is, what I refer to as a "cam over" action in the lock mechanism.
When you push either the key fob button or the button on the door to lock or unlock the door
the door lock actuator "throws" the lock rod for and aft. If the lock assembly pivot doesn’t get thrown far enough, it tends to stop in the middle of it travel. Not quite over the hump as it were. Then, all it takes is for the hapless owner to somewhat vigorously close the door and the lock pops back to the locked position. A bad thing if, say, you have left the keys in the ignition… with the engine running… while pumping gas into the car… anyway…

Over time the parts wear, the linkages loose whatever lubricant originally put on them, and, or, they gather grit and grime so that they don’t function as the did when new. To clean the linkages and pivot points, first remove the door panel and give them all a good shot of WD-40 or similar and cycle the locks several times. Give extra attention to the top of the lock mechanism as shown by the left hand red arrow in view B of the Lock assembly figure. This is where the "cam over" action takes place. To gain access to the top of the lock assembly, remove the rubber filler piece at the end of the window sealing strip. (See view B, item #2 in figure 7) Just spray straight down on top of the lock assembly. The lube will penetrate and go where it needs to go. No need to remove the assembly unless your feeling really ambitious. To insure that the locking mechanism remains trouble free, give all moving contact parts a good shot of some aerosol grease. I used BD Heavy Load Red Grease because I had some on hand. It sprays out in a semi-liquid form due to it’s suspension in a solvent. This enables it to penetrate and mix with/ replace the WD-40. When the solvent evaporates all that is left is the grease.

I’ve used the white lithium grease long, ago in a land far, far away and found that it just seems to clump up and dry out. Don’t use it any more. For anything. The FSM recommends Lubriplate ™. I don’t. Used that stuff 30 years ago. Don’t know that anyone does anymore but, some grease is better than no grease.

This procedure will work so long as the lock actuator is functioning as it should and there are no other issues such as broken or bent parts. It’s my guess that some may purchase and change out the actuator when all that may be necessary is a good cleaning and lube.

It’s been over a month since I did this and I haven’t had the door lock on me once. It used to be a once, maybe twice a week occurrence before that.