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Door Lock Actuators

Big T

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Location
Fullerton, CA
I replaced the driver's side 2nd door due to a developing rust bubble. Also the lock actuator was not working. While removing the wiring harness, it was apparent that the door lock actuator had become detached at the rivets (original door). I was hoping the new (old) door would also have a good actuator. Turns out that actuator had also detached with the rivets pulling out. I drilled out the rivets and mounted with bolts and nylock nuts. Prior to doing all of this, the driver's door, front passenger and 2nd passenger side door actuators all worked. Now only the driver's front and passenger 2nd work. I can see some movement on the other two door lock, but not even close to locking it. Are these just worn out actuators? Gummed up rods?

I'm going to pull the actuator from the old door and test it on the harness to see how strong it is.
 

So after doing some tests using the old cut harness direct to a battery, I determined that the actuator from the “new” door was pretty weak. So I replaced with the actuator from the old door. After cleaning up the actuator rod, spraying up the door latch mechanism and working the slide button over and over again, I got the actuator to work. However, it seems like it will full work 3 or 4 cycles then stop in the middle as in the video above. Wondering if the actuator motor is weak, heats up after a couple cycles and loses some strength?
 
Got the new actuators, manufactured by VDO. One did not work right out of the box when tested using the old cut harness direct to the battery terminals, the other did. Installed the working one and it's fine. Returning the non-working, which means I won't see it for two weeks and I'm gone on vacation for two weeks. Then I'm working in SF for 3 weeks. So this will be delayed, which is typical.
 
Actuators in the doors on the K3500 act just like what Yours is doing. I thought about replacing the actuators but just wanted to be sure it was actually the actuator and not a possible bad ground, within the door or on the door itself, grounding through the hinge pins and no ground wire within the harness or a possible bad relay switch. After reading Your posts, it seems that it most likely is the actuators themselves. That`ll be a project for this winter, if I can get enough moooolah together to gettum. LOL
 
Actuators in the doors on the K3500 act just like what Yours is doing. I thought about replacing the actuators but just wanted to be sure it was actually the actuator and not a possible bad ground, within the door or on the door itself, grounding through the hinge pins and no ground wire within the harness or a possible bad relay switch. After reading Your posts, it seems that it most likely is the actuators themselves. That`ll be a project for this winter, if I can get enough moooolah together to gettum. LOL

The harness plug to the actuator is simply 2 leads that reverse polarity to move the rod in and out. The motors in the actuator clearly weaken with time. Also, the actuator rods gunk up where they slide through plastic clips and need to be cleaned and new white grease applied.

The actuators are riveted in place. Those who’ll need to be drilled out of the mounting plate which then gets transferred to the new actuator. To remove the actuator, detach the slide from the rod and then wiggle/rotate until it drops straight down inside the door. You cannot get clearance to move it forward to remove from that access hole. Unclip the wire harness and install on the new actuator and shove back up into place. Install with two bolts and nylock nuts. Test before closing up the door. With experience it’s about a 30 minute job. Actuators I bought were $24 at Rockauto. There were some around $18 but they were mystery manufacturer. I’m familiar with VDO and yet I still got a bad one.
 
The harness plug to the actuator is simply 2 leads that reverse polarity to move the rod in and out. The motors in the actuator clearly weaken with time. Also, the actuator rods gunk up where they slide through plastic clips and need to be cleaned and new white grease applied.

The actuators are riveted in place. Those who’ll need to be drilled out of the mounting plate which then gets transferred to the new actuator. To remove the actuator, detach the slide from the rod and then wiggle/rotate until it drops straight down inside the door. You cannot get clearance to move it forward to remove from that access hole. Unclip the wire harness and install on the new actuator and shove back up into place. Install with two bolts and nylock nuts. Test before closing up the door. With experience it’s about a 30 minute job. Actuators I bought were $24 at Rockauto. There were some around $18 but they were mystery manufacturer. I’m familiar with VDO and yet I still got a bad one.
Thank You Big T for the infurmashun. I`ll probably wait until this winter to mess with those. Working during the summer so when I`m not working I try to not do a thing. LOL
 
Thank You Big T for the infurmashun. I`ll probably wait until this winter to mess with those. Working during the summer so when I`m not working I try to not do a thing. LOL

I normally work on my truck during the winter because summer is fishing time, but I’m still recovering from some fairly extensive foot reconstruction surgery. Had some nerve damage as a result and here I am 9 months post op and still struggling. So i’ve been catching up on some minor things on the truck.
 
Because this is a truck site, I’ll explain in truck terms. This was a realignment job to correct an ankle that became misaligned as a result of unknowingly walking around for 18 years on a completely torn peroneas brevis tendon and several partial ligament tears. The injuries were the result of 4 different ankle sprains suffered while playing competitive tennis. Back when the sprains happened, they took x-rays which showed nothing broken, but MRIs were just coming out and very expensive and insurance never paid for them. So they handed me crutches and a bag of ice and sent me on my way. Over time the ankle became unstable and rolled to the outside. I had the tendon repaired two years ago. That repair took but resulted in new pain below the repair site. Never saw that surgeon post surgery, only his NP who was somewhat dismissive in saying the pain was normal and it will go away in a year. It never went away and I’ll be damned if I was going back to see that nurse again. So I sought a second opinion and was referred to the surgeon who handles foot and ankle injuries for the Lakers and teaches at USC medical school.

First visit, he says the prior surgeon did not address everything. He explained, described my options and basically said if I did nothing, the repaired tendon and the ankle joint would eventually fail if not addressed. Great, so what do you need to do? Saw off your heel (Calcaneous Osteotomy) and slide it to the outside to align it with the weight load. Saw and remove a bone wedge (Osteotomy of the 1st Metatarsal) from the big toe to lift it. Mechanically it came out pretty good as shown in the before and after x-rays:

4DD279B4-419C-4836-ADD8-5D994ED8ECBC.png9CB85DA1-A325-4B51-ABD4-058E8EB618E2.jpeg

Unfortunately there was some nerve damage due to the extreme movement of the heel that was needed to achieve alignment. Most will recover, but slowly. The tibial nerve is entrapped in scar tissue where the hardware was installed in the heel. That has the entire heel pad numb. Eventually that will need to be addressed with some minor (relative to the bone saw work) surgery.

This surgeon has handled every post op visit himself as he truly cares about the results of his work. I’ve sent him messages through the patient portal and he calls me when he gets out of surgery or leaves me a voicemail. Because this is a mechanical repair, I talk shop and thoroughly explain what i’m feeling often in the respective medical terms as I’ve read up on it. Though it’s not the perfect outcome as yet, it will get there. Most of the appointments my wife goes with me to serve as a second set of ears. This guy is methodical, fast and really knows his stuff.
 
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So I returned the failed actuator and I guess the shipment triggered the shipment of the replacement part as I got it today. Now I know exactly what the problem is. The male end electrical connections are not fixed in place and push into the part when the harness plug is installed. You can see on the new part on the right that the male electrical ends are pushed more than half way down into the part versus the old part on the right. I tried pulling the male ends out with needle nose pliers and then connecting the harness plug. Now one male electrical male end is pushed completely into the actuator and is not retrievable.

0428D30E-AB6F-4D96-9292-C1ADAEE54D93.jpeg
 
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