Rear Door Lock

One of the power locks on the rear of my crew cab has not worked as long as i have had the truck. I started digging into it some today and it doesnt seem like the motor is trying to unlock it at all.

I was trying to determine if it was getting power but wasnt entirely sure exactly how to test the wiring. I am looking for some input on how to test if its getting power to the door, as well as any other troubeshooting ideas.

Thanks in advance fellas.

test light or volt meter

Yes, but what specific wires do I test? There are two going to the unlock motor, but i dont know how the polarity works with lock and unluck, or if there is a common ground. I also tried to test continuity but wasn't sure how all of that should normally act, ie across the motor, and towards the switch. If I would have had more time yesterday I would have pulled off the other side that works to compare, but didn't have time.

The actuators are crap and they are cheap. I would bet it is the actuator.

That seems to be the general consesus from my searches, but I expected there to be some evidance it was trying to work, just not well enough; but there is no evidance what so ever. Thats probably where I will move on to next. Thanks for the replys guys.

There are two wires going to the actuator. Trying to move it one way (say "lock" for example) will give +12V on a DVOM and trying to go the other will give -12V with the DVOM leads in the same position. If you take the actualtor motor out, you can put voltage to the wires and see if it spins. Cheers!

Thanks for the info! We'll see if I can get to that tomorrow .... inlaws are in town.

Alright ... I have somewhat of an update. I got to the actuator and ended up just pulling out. Upon inspection, it turns really hard and sounds crusty inside. I know many have been able to take it apart and fix them, but it seems like my issue is different from the issue other have been able to fix. Also, I don't see how to get mine apart to do the fix. What do you all think ... just get a new actuator?

cant go wrong with new. I aint saying you dont know what you are doing but do you know what you are doing or do you think you will just fack it up more? With a new one you can get 10 years plus out of it ( on good conditions)

I am not too worried about breaking it since it didn't work before ... with that said I am going to try and remove the motor and see if its bad or the part that goes up and down is junk. Do I know what I am doing? We'll see, but I do know enough to design farm equipment ... scary huh?

good luck, pos tup how it works out

Here is a picture of the actuator cylinder (maybe not, haven't ever done it from my phone) .... pliers didn't work, now there is some missing plastic, no biggie.

Will try more invasive methods later. Time for bed.

On mine I driled out platic rivets rivets, opened case.
Pulled out a small flat plate replaced it with a cut up canadian penny.
Ziptied it and remounted it....

Google penny door mod.

I bought an actuator motor for $10 (new factory Ford from something else), swapped over the actuator rod from my old one. Cheers!

Well, I did some research online yesterday and determined that the actuators for the rear doors in a crew cab are different from the front ones. Looking online at Ford Parts it seems that the front actuators are in the area of $95 and the rear actuators are $330! Holy Chit thats a lot of money, and I am definatly not paying that. I went ahead and ordered one off of Ebay for $7.95 that is a "Unviersal" actuator, and I think I should be able to make it work.

For the hell of it last night I decided to try and get my old one apart to see if it was repairable, and just how it worked (why it was so F-ing expensive). I used a reciprocating saw to cut slits into the crimped on part and then bent the tabs back. I was able to get the plug out see what was in it and took a few pictures. This type of actuator doesnt use a small electric motor like many of them do, this thing actually IS the electric motor, and apparently got some water in it because it was rusty as sh*t in there. I snapped a picture of the inside and then all the parts just to show what it actually is. I think its too far gone to be able to fix it, especially if I can get this one for under $10 to work.

I will keep you all updated when I get the new one on how the install goes just to get some more info out there.

Read my post above again. If you see how the rod is attached, you can easily swap in your old one on the new motor (the motor part of it is going to be pretty generic to many Fords). Cheers!

Yeah, I saw that, but I couldn't find any for less than $35. Not that its unreasonable for that, but I have seen where others have made the universals work. If this doesnt or it seems chincy then I will definately be retro-fitting an actuator from a different for vehicle. I don't feel too bad since it was so cheap. Thanks again for the input.

Got the replacement actuator today. We'll see if I can get to it tonight or tomorrow night. I attached some more pictures to show what the new one looks like. Should work .... the only potential issue I see would be that it seems like the old one might have a bit more travel than this. I think it will work like a champ though.

Got a little done tonight. Going to be able to leave the factory plug on it in case I have to use a ford replacement for some reason. Got it mounted, so now I just have to get the rod itself figured out and should be good to go. If people don't want this much detail just let me know. Figured since it wasn't the usual "door lock fix" I would try and help someone else out by putting up as much info as possible; since I have gotten so much help from others thought I'd try and return the favor.

SUCCESS!!! Finished up the install tonight. Went a lot faster than I expected it to. I had it mounted in the door yesterday, but pulled it back out and used the old actuator and rod to figure out how long the new rod needed to be, so they were the same length. Some quick forming work to make the rod match, viola, it worked like a champ. I attached some pictures of it mounted inside the door, but the quality is incredibly terrible as i was holding the phone/camera blindly inside the door. Not a bad fix at all, aside from some tight spaces for working, luckily my hands aren't all that big. It took about 4 seconds of having all 4 locks functioning to lock myself out of the truck. ointlaugh: The front door swung shut right as i was thinking ... ah crap. I am glad I finally got around to fixing it, and that it I was able to make it work fairly economically. This is one of those things that really bothers me (the locks weren't symmetrical). On a side note, why don't they have factory replacement lock rod covers at auto parts stores? Do that many people actually put skulls or 8 balls on them?