Do-It-Yourself Door Lock Actuator Repair

[heykerrdog]

If you've been saving up your money for new door lock actuators because everything that you've done to troubleshoot itermittent and weak actuators has led you down the rosey path of "it must be the actuators, everything else checks out fine", well, here's the free fix. Not my idea, but it works and it costs you nothing. If your actuators are weak, inconsistent, flakey, you name it, they sorta work but don't have enough "umph" to move the locks, then get out your torx sockets, Dremel or drill, plastic melting tool (I used my soldering iron to melt the plastic and plastic-weld with it), whatever, get creative, there's a lot of ways to skin this cat. Above all, aluminum foil.

I took a couple of pics. Here's the deal. From Ford Truck Enthusiasts website.

Power Door Locks FIXED!!!! - Ford Truck Enthusiasts Forums

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WARNING: The following is long winded, but if you want your PDL's to work again WITHOUT spending any $$ read on.

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I finally got tired of my non-working PDL's and decided to tear into my truck and find/fix the problem. There has been many discussions about possible issues and I have concluded that the majority of us are seeing actuator motor problems and not relays, switches etc. Ill start by saying the problem I have had is that when I hit the switch, the locks attempt to move and after repeated attempts, the signal appears to get weaker and weaker until nothing....I assumed relay or switch.....NOT THE CASE!

First I started by testing the signal at the harness plug to the actuator. Perfect. No issues here. Next I completely removed the actuator/lock mechanism and bench tested them with 12V..Here lies the problem. The actuator acted the same as when in the truck. First I did a thorough cleaning of all of the mechanism so it works freely and still had the same results. Here's where it get's tricky. These things are built so that they are NOT serviceable. I had already decided that they were going to need to be replaced, so I decided to break them open for closer inspection. It comes apart relatively easily, but appears that It cannot be put back together once apart. I drilled out two small rivets and then pried the case apart. As you pry the case apart you'll notice these small little plastic rods protrude up through the case cover. These rods are then "mushroomed" with heat through the upper case and then sealed with some kind of silicone. When you pry apart the case the "mushroom" head breaks off and the rod remains. You can dig out the silicone and mushroom head with a pick. It comes out very easy. Inside you will find a very small motor and some gear mechanism. I believed the problem at first to be worn brushes or dirty commutator contacts in the motor itself. You'll have to bend two little metal tabs out and pull off the brush housing on the back of the motor. I cleanded the gunk off the brushes and took 1500 grit to the commutator contacts and reassembled the motor. The motor worked, but if you applied even a slight amount of resistance on the armature, it would stop the motor. It should have been WAY stronger than this. I was stumped until I looked a little closer at the inside of the plastic brush housing. Inside you'll find a small, thin rectangular (thermal resistor relay, dodad, thingamabob??) pardon my ingnorance, but I'm not sure what to call it. All I know is that this little part is what keeps you from burning up the motor, should you continue to press the switch once the lock has been actuated. It appears that this thing wears out over time and will not allow enough signal to get through to the motor to make it work. THE FIX . I am cheap. Since I had done so much work up to this point, I decided that I would go a little further and try to make it work without spending the $$. I have better things to spend my money on than actuators. I took a small piece of aluminum foil and wrapped the "thing" voila! Perfectly working motor! I sat there and operated the thing for 10 minutes including one or two times stopping the armature and holding down the switch to see what would happen. The motor builds heat, but not much. Not enough to worry about. Now that I had a good working motor I decided I would try and reassemble the unit. The problem is you cannot glue the unit together as there is a rubber gasket around the perimiter of the case and if you tried to glue the rods into the case, you would not have enough pressure on the two halves of the case to keep the gears in place (these things actually apply a great deal of torque on the case) What I decided to do is completely break off the plastic rods flush with the bottom side of the case and then drill out the bottom case and screw it together. This worked perfectly. You'll need screws that are the same diameter as the holes in the top of the case to keep it from "wandering". Also the screws should not protrude through the back of the unit as some of the mechanism has some pretty close tolerances and a screw sticking through the back would not allow some of the mechanism to work (this can be remedied with a decent set of wire dikes or a hacksaw). I know all of this is hard to picture, but if you do decide to try this fix, you'll see what I am describing here. The locks are back in and working flawlessly.
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I tried a few different disassembly/re-assembly processes. What worked best for me was a Dremel. The two rivets are tough to drill because you can't hold the rivet still from spinning. I simply spun the rivet until it got hot and pushed through, then reinstalled pop-rivets. For the plastic, I used a screwdriver, pryed all the clear yellowish glue off with a small screwdriver, Dremeled the plastic "heads" flush, then opened the actuator for the repair. In reassembling, I used my soldering iron and poked the plastic standoffs on center, which melted them, forcing the plastic to come up and outward. I then melted some of the same plastic that I had laying around from a crashed motorcycle and added it to the already melted standoff plastic to form my own plastic "heads".

Some items to save you the hassle of broken parts and having to back up and re-open the door panels because you "forgot" to hook something back together.

- the door panels lift straight up. don't pull on them. don't force anything.

- two screws. one behind the lens. one behind the switch panel. then the door panel will lift.

- front doors have a trim piece at the sideview mirror that must be removed before the panel will lift upward. pull straight toward you.

- the switch panels simply lift up. the back doors, lift the switch up where it is closest to you inside the truck. the fronts, lift the switch up closest to the door jamb.

- one rod on each actuator needs to be removed inside the door. be careful with the yellow clip. simply rotate it away from the rod where it is clipped onto the rod, then pull the end away from the actuator and let the rod stay inside the door.

- the inside and the outside door handles come off easily. inside handles have two screws. on the back doors, pry the hinged black cover downward to expose the screws. the front two are already exposed. on the fronts, pay particluar attention to how the cable snakes through the door and around the lock rods and window tracks so you run it back through without interference. be careful with the little yellow plastic clips that hold the cable to the inside of the doors. squeeze the little points and push gently. outside handles have two screws. a black rubber plug on the door gives access to one of the screws.

- front door handles have door key locks with a metal rod. to disconnect the metal rod, be really careful when you pry the plastic clip fingers so you don't break them. both of these clip fingers have to move together to pull the rod out. the lock rod stays connected inside the door. there may be a better way, but I didn't see one at the time.

- two electrical connectors at each actuator. one for the actuator motor. one for the dome light. be gentle. Also, I found it easiest to pry the wire loom push clip off the actuator to give me more room to pull the actuator up so I could access the two connectors. Particulary the front doors, where you can disconnect the wires connectors after you pull the actuator up and out of the door handle hole.

- to pull the outside door handles off, you have to maneuver the door handle to follow the contour of the actuator rod. it's S shaped, and twisting and sliding with allow you to pull the outside handle off the rod. No clips on this piece, just a yellow bushing. Don't scratch your paint with the door handle threads.

- don't forget to run your front door light wire back through the vapor barrier and reconnect it to the door panel.

- the vapor barrier peels off the door, but be gentle and peel from different directions when it stops cooperating.

- the plastic door lock actuator assembly slides off of the door latch by prying a clip on the plastic actuator up and sliding the actuator off the latch guides.

- when you crack open the actuator, there aren't any booby traps. no springs shooting out or anything. it's pretty straight forward.

- be careful with the motors on re-assembly. I used a jeweler's screwdriver inserted through the outside slots to hold the brush springs out of the way. also, look for any small plastic washers that may have slipped off of the armature and reinstall them.

[MrJohnWayne]

I'm gonna give that a try on mine! My passenger side door locks work when they fill like it and it irritates me.

[Maintain]

Wow nice writeup...