When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I figure this is as good a time as any to investigate an issue I’ve been having every winter since I bought the car. During cold temps, usually below freezing, the door lock actuators tend to fail to unlock the doors. This is especially apparent for the rear doors, but it also happens to the front passenger door often, and the driver’s door the least out of the four doors.
Sometimes I’ll see the inside lock lever bounce a bit when unlocking the doors (remotely of course), but not high enough to actually unlock the door. Is there any adjustment for the adtuator’s mounting position, to be able to slide it higher in its mounting, perhaps? Or maybe file the mounting holes in the door panel into slots, to allow for upward movement of the actuator to eliminate the slack?
Is it due to old, weak actuators? Play in the linkage?
For what it’s worth, with the locks locked, the driver’s lock pin sits much higher than the passenger side front door, and much higher than the rear doors. Could this be some proof that actuator mounting position would cause this problem?
I would pull all the interior trim panels and lube the lock/latch mechanisms. I had to do this on hundreds of cars from the XJ sedans from the 1960s to the X308 over the years. The rear doors on my 1992 seemed more susceptible to this than the front doors.
My back doors on my 1999 and 2001 seem to need lube every few years. They make noise and the lock knob 'hops' but sometimes the lock 'sticks'.
You can try to 'cheat' and lower the windows completely, then spray PB Blaster, Liquid Wrench, Kroil, CLP etc. at the back of the opening (down onto the latch mechanism).
Removing the door trim panels is the best way to ensure you get everything lubed and functioning.
The actuators do fail occasionally and if the unit is DEAD then replacement is required.
In addition to Bob's excellent advice, I have also discovered that the upper sections of plastic interior trim panels sag over time, causing the top panel to tilt. This causes the chrome bezels that fit around the lock pins or buttons to tilt and bind on the pins. You can test for this by removing the chrome bezel (part 12 in the diagram below) from the upper trim panel, then testing the power lock operation. I can't remember if you can pry the chrome bezels out with the trim panel installed and the lock button protruding through the bezel. If not, you may have to remove the upper trim panel, but this is easy: Remove the black plastic flap from inside the door latch handle cup, remove the Phillips head screw under the flap and lift the black cup and chrome handle surround away. Carefully pry the front edge of the wood veneer trim away from the door and then slide the trim piece toward the front of the vehicle to unclip it from the door. You'll then see a few Phillips-head screws that must be removed before the plastic trim panel can be lifted upward off the lock button and edge of the window.
If you find that the lock works better without the chrome bezel in place, you can use a heat gun to carefully warm the plastic trim panel and reshape it so the upper edge sits more horizontal. It can also help to lubricate the inside of the chrome bezel with silicone grease (dielectric grease, O-ring lube, brake caliper grease, "personal lubricant," etc.).
P.S. Once you have the top trim panel off, removing the lower main trim panel is just a little more work. If I recall, there are a couple of screws hidden by plastic caps on the underside of the arm rest/handle, and on some years there is a screw inside the puddle lamp at the bottom rear corner of the door - you carefully pull/pry the lamp out to reveal the screw. Follow Bob's advice to lubricate the actuator, linkages, latch mechanism, door handle, etc. For this I like the white lithium grease that comes in spray cans with a straw type nozzle so you can direct the grease exactly where you want it, and the white lithium grease seems to stay in place better than other types of lube.
Well I certainly have a couple good leads to follow now. I never would’ve thought panel distortion would be the root, but this certainly could be the cause.
I’ve had these door panels off more than I’d like to remember, and I have tried lubricant the lock mechanisms but that hasn’t helped.
Any suggestions on types of lubricant for the mechanism? I have silicone lubricant, dry lube spray, white lithium spray, etc.
If I recall correctly, there was quite a bit of play in the plastic lever attached to the lock actuator, at the point circled. I tried twisting the metal tab in the plastic slot, and that did help to remove a bit of slack, which helped operation. It seems like if I could remove all slack from this point, the locks would work fine...
12-23-2018, 06:28 PM
Door Lock Actuators Weak in Cold Weather
