Fixed: Door Lock Actuator in Gen II Prius

Hi everybody,

I don't post much to forums like this, but I put so much research into fixing my 2005 Prius Gen II door lock actuator that I thought it should be documented.

Do this at your own risk... the actuator has several moving parts inside, and if you can't make sense of how little mechanical things like this work, then you might want to avoid the whole thing.

Total cost: $5 for a new Mabuchi motor. A new actuator assembly (for the front driver's door) costs hundreds but from what I gather, replacement of the little motor inside the actuator is usually a solution.

Several websites document the removal of the door panels. I will show the fix for the front passenger door, but I've done it for the driver's door as well, and the process is the same. All door actuators use the same motor.

First you need the motor. Ebay is the best bet, because most other vendors sell them in large quantities. Get the Mabuchi motor with a 20mm shaft. It's about 1mm too long, but that's the closest I could find. The image below shows a vendor with the part number and the long shaft as an option.

BE VERY CAREFUL -- the part number does not seem to distinguish the long from short shaft models. The Mabuchi motor needs to have the FC-280XX-2215 (the XX varies from item to item. I thought that PC meant "long shaft" but I don't believe that anymore).

Anyway, find a website to show you how to remove the inside door panel. I won't take space up here for that.

Make sure the door's window is ROLLED UP.

You'll need a TORX driver to remove the three screws holding the actuator in place.

There's a little mini panel that provides access to the actuator. Remove it.

There's a bolt holding the lower part of the window's guide rail in place. Remove it.

The guide rail just hangs now. You can now push this window guide rail out of the way, as it blocks the removal path for the actuator. The image below is looking up through the access hole into the door. I'm pushing the guide rail up and out of the way.

Unplug the actuator cable.

There is a manual locking rod that runs through a lever on the actuator. I didn't take a picture of it (doh!). Regardless, the actuator needs to be lowered downward to disengage it from this rod. The rod just falls out, but have a look at the whole thing before you pull the actuator out, because you'll need to get that rod back in when reinstalling the actuator.

Wiggle the actuator out through the access hole. There are two manual operation cables (for the door latch and lock) whose attachments are behind a little black plastic door on the actuator. Carefully pry the door open. The cable with the blue end is removed by lifting it up perpendicular to the surface. The cable with the yellow end turns 90 degrees counter-clockwise, then lifts up.

Now the actuator is out of the door. Find a table to work upon where you won't lose the little parts. Remove the screws that are numbered 1 through 5 on the case.

There's another smaller screw that needs to be removed, pictured below.

There is a funny cover that needs to be removed. It's held in place by clips. Remove it CAREFULLY, as it looks easy to break.

Now there are sooooo many little clips on the outside edge that need to be lifted simultaneously. Be careful, and note that some prying will be needed to keep clips from closing after they've been released.

BEFORE OPENING the case, turn the actuator over (so that the side pictured *above* is facing downward). This is important because there are parts that will fall out if you open the thing upside-down.

Here is the inside of the actuator. There is a little plastic electric panel that needs to be removed before the motor can be taken out. The panel is held in place by two screws, I'm pointing to one below, and the other is on the lower right of the panel (not visible in the picture).

The panel has two electrodes that plug directly into the motor, and are removed by gently prying them upward.

The motor just lifts out. Try not to mess up the grease on the little worm gear. If you do, it probably will need to be greased again. It may need a synthetic grease since this is plastic, but I'm not sure.

I decided to test my motor. This is one way to do it. A 9 volt battery is strong enough to turn it. Reversing the +/- polarity reverses the motor.

My motor was WORKING. I didn't know if it was my problem. It turns out that, while it did turn, it didn't have enough *torque* to unlock the door. I discovered this by trying a motor from one of the other doors (yes I took another door apart and moved a motor from one door to another), and upon reassembly, the actuator worked fine.

Gently pry the worm gear from the old motor. Notice that the motor shaft is flattened. The one that I got in the mail had a rounded shaft (not flattened) that was 1mm too long.

I put the new motor in a bag that I sealed (to protect the motor from metal filings that were about to be produced -- the magnets in the motor could attract those), and pushed the shaft through a side of the bag. I shortened the shaft by clipping off 1mm with a pair of strong wire cutters. The end of the shaft was sharp now, so I smoothed it with a file. Next, I carefully put the shaft in a small vise (see below). In the image, I've already started flattening one side of the shaft.

I marked off the length of the shaft that needed to be flattened, then started filing with a metal file. I was very careful not to push down on the motor or bend the shaft!!

The vise was important, because it allowed me to file the shaft without bending it. The resulting motor looked just like the image displayed three pictures up (in fact, that's the newly prepared motor). Use your old motor as a guide for length of shaft, and how deep the flattening needs to be along the shaft's end. Make sure that everything is smooth and without metal barbs before attempting to press the worm gear back on.

After a few trials, I was able to press the worm gear onto the newly shaped shaft. Before removing the motor from the sealed bag, I made sure that all metal filings were cleaned away.

Reverse the extraction process above to put the whole thing back together. Be careful to:

• Get the actuator snapped together properly. If it doesn't snap together easily, then something is misaligned inside. Remember the little latch that the manual door operating rod went through? If everything is aligned properly, the latch should swing freely across its entire range of motion.
• Don't forget to put the manual door operating rod back into the latch when reinstalling.
• You can test the whole thing without reinstalling everything by plugging the electric door control buttons (from the door armrest) in again, and the actuator to its manual cables and electric wiring. Press the little rubber button that gets pressed by the door when it's closed. This will make the car think the door is closed. Try your remote and see if the actuator latches and unlatches as it should. If it doesn't, think about taking the actuator apart and realigning everything.

Good luck,
Scott Guth

Hi, Scott. Are you talking about the problem with the doors not always locking? I have that problem on my 2008. I mentioned it to my service man at the Toyota dealership but of course he could find nothing wrong. It will only refuse to lock about once every 50 or so times. I just keep going to another door until I hear the confirming "beep" indicating the doors are locked. There wasn't a recall for this, was there? I'm definitely not a DIY person. Thanks.

Sorry, I just uploaded the images.
Scott

That's how mine went bad. It failed to work from time to time until it never worked again. I don't know if there is a recall for this. I did take it in first, and they told me it wasn't covered.

That is great info. I like the cheap DIY fix.
Just one comment: your pictures are ~2.5Megs each, so this page ends up being a real download for those of us not on a very fast connection. And being that they will be displayed on a screen, not printed, there is no loss in resampling the images down to a reasonable size. Often forum software does this automatically, but not this one. Modern cameras generate high density images, way beyond what is needed for screen resolution.

Okay, I replaced the images with smaller ones!
-Scott

I've learned TWO things in this thread! Thanks!

And Scott - Thanks for your documentation. I recently had to do door surgery on our Hyundai and could have used a similar write up then. Needless to say, I'm bookmarking this thread.

I just wanted to share that I found this thread last week, ordered the motors, and decided to do it today. The only problem I had was in the panel removal - a few clips broke but it all looks great after reinstallation. It took me an hour to do the whole thing. This is one of the best-documented things like this I've seen. I'll add that the hardest part for me was realligning the rod through the actuator on the back as I reinstalled it. Opening and closing the door handle from the outside while I wiggled it into place made the difference for me. I used a bench grinder for a very quick shaft conversion - great idea to cover the assembly with a bag. I really appreciate the time you took to post this. I'll do m rear right door sometime too but the driver's door is back to perfect. "Internet high-five" for posting this.

What an awesome write up for us DIY guys. Another great example of how things can be fixed on the cheap if you're willing to DIY. This would likely be a $200-$300 fix at the dealer (if not more). And... from what I can tell, this is applicable to all Toyota, Lexus and who knows what other cars.

Thank you Scott for the awesome write-up.

Great Article, Thank you VERY much. I did the back doors as well and they ARE VERY different inside.
My first back actuator basically exploded apart and I had to re-assemble without any docs/pictures
ALSO: I had to put pieces 1,2, 3 and 4 (seen in top half photo) together and through the slit in the top half while putting it together with the bottom half......I am uploading the photos to help others
Thx,
Jon

Thanks, Scott! I successfully replaced the motors in the two front doors of my 2008 Prius this past weekend, thanks to your post. I found it two weekends ago and ordered four motors off of eBay (Mabuchi model #FC-280PC-22125). I had to shorten & flatten the shafts with a file as you described, although I couldn't get my vice to grip the shaft properly. I held the shaft with a pair of needle nose pliers (required an extremely firm, straight, and careful grip) while I filed (also required keeping the file very straight). It’s great to have working locks again. Definitely better than coughing up around $300 a pop for new actuator units.

Over a couple of months’ time, both of my front door locks had started failing, with increasing frequency, to respond to my remote or to the power lock/unlock buttons on the inside of the doors. They had finally stopped working completely. One of the rear ones is now beginning to give some occasional trouble. As I had gone ahead and bought four motors, I will be tackling the rear two motors soon. I am considering checking to see if a local machine shop can flatten the shafts on those two for me before I install them. That would really make it a snap.

I do have some comments to add to all of this. First, when unsnapping those numerous plastic tabs, I inserted toothpicks into each tab as I unsnapped them. This helped to keep them unsnapped as I moved on to the other tabs.

Second, when reassembling the unit, it is easy for the slotted metal bar near the center of the unit to fall off of the part that its slot fits over. Before re-assembly, be certain to put it back over the part it slides over. As you mentioned in your post, make sure the little latch lever that the manual door operating rod goes through, as well as the metal lever that the cable hooks to, are aligned properly. Both levers should swing freely across their entire range of motion. The cable lever, when swung as if pulled on by the cable, actually depresses the manual rod lever, although the reverse isn't true. I had to do it a couple of times and unsnap the whole thing again each time before I got it right.

My third and final comment has to do with the key lock cylinder rod on the driver’s side door. I at first didn’t realize it existed and had to be reinserted into the actuator unit when reinstalling it into the door. It was difficult getting it lined up right to fit back into the unit without feeling like I was going to break the rod off – which may be a real possibility. I had to completely remove the metal part of the window guide rail (it slides right back over the rubber) to get a little more maneuvering room, so that I could twist the actuator unit into position enough to guide it over the end of the key lock rod. There is a kind of funnel shape to the portion of the actuator unit’s plastic housing around the hole which the key lock rod fits into. The funnel only goes about halfway around the hole. I had to twist the unit into a position such that the funnel half went behind the key lock rod and the rod could kind of slide in on the non-funnel half.

Despite this trickiness, this has got to be one of the most worthwhile DIY procedures that exists for the Prius. It is saving me nearly $1,200 for the parts alone, for the four door locks. I hope you keep posting great ideas on this forum!

Well, I did the rear units yesterday. As jfkaiser said, they ARE different.

First, they were a little harder to me to maneuver out of the door. I had to twist the window guide rail about 90 degrees to get the unit by its end bracket. I first tried to remove the rails but could not figure out how they were attached at the top. Happy they did not break! At least there was no separate metal panel to remove for the rear.

After inserting the new motor (no screws or circuit boards to remove & replace for the rear motors), I assembled part nos. 1, 2, 3, & 4 (as so labeled in jfk's photos) into the top half of the housing. The cable lever goes through the slit, and you must take care that the white plastic stud of part no. 4 goes through the slots of part nos. 1 & 2. The grease actually seemed to help hold them in place during reassembly. Not sure, but I think it is best if the black plastic child safety lock is in the unlocked (up position when installed in the vehicle) position. You must also take care that the tab of part no. 2 is installed so that, when the cable lever is pulled, it will be able to press against the lever which actuates the heavy metal latch of the actuator unit.

Ensuring that all the other parts (levers, gears, springs) in the bottom half remain properly seated is, of course, very important. Study jfk's photo if necessary, and take special care that the springs seem to be situated properly. There is one I call a jaw spring that makes the lock click in & out when a plastic stud moves in & out of it, and there is a round thin wire tension spring, with a straight portion that nests behind a metal lever, which returns it to position after it is moved. Good luck with all this!

Sure, this is a tricky repair, but for the more patient & determined DIY'er, with good mechanical comprehension, it is a tremendous money saver. Just know your own limits, and seek out a little help if you need. Thanks again to Scott and jfk!

Scott, what a great write up. The pics are perfect! I am going to print this out and put it in my "Big Book of Prius" and I will have the fix data. I ordered 2 motors, $5 ea, I will set aside, they will come in handy some day!
+1

Well I love this write up its really good! But, I must confess, I screwed up some where. I got the new motor in place etc and the electronics for the door work great, but I may of hosed my self by having the latch in the door mechanism in the wrong position. I closed the passenger door and can't open it from outside or inside. The mechanism shows it "unlocked". I even stumped the locksmith friend of mine, he suggested it's probably the latch. So I'm going to have to drill a hole from the inside to the latching area and see if I can unlatch it. Any other sudgestions?

Ok got the door fixed, this what happened, I had to drill a hole through the inside(behind seatbelt post area) to where the latching mechanism is. My locksmith friend still had a very hard time opening, but what he was doing was pushing down on the door over n over wile trying to open it with the handle. It finally opened. Now I took the lock mechanism apart again and what happened was that something was not aligned. Be sure you take photos so you have a reference to go back to incase you drop it. Also a quick tip wile trial fitting to make sure things are aligned up, you can use tape on the plastic clips so they don't clip in place so you don't have to break your nails pulling them apart again.

Trial test over n over to make sure when you simulate you lock you can push down on the door handle tab and it opens and also the little C thing under the little door that holds the cables for the interior mechanism BEFORE putting it back in the car.

Also when putting back into door the exterior door handle rod if I'm correct should go through that little metal thing with a half bowl plastic. Good luck all

To the original poster.
That is what I call a tutorial A++.
Job well done.

Well I have to say these instructions worked very well. I did both front doors and the new motors work a charm. Alas I made the same mistake Los did, I got the latching mechanism switched up somehow, and stupidly closed the door. In my case the driver's side. Now I cannot get the door open. You can unlock it, but it will not release the lock inside the actuator mechanism, meaning nothing can unlatch the door. Ug!

Make sure you test the latching mechanism BEFORE you reinstall!

I've ordered a replacement actuator unit from ebay, and when it arrives I will see if I can replicate my mistake on it before moving forward. I have no idea how Los opened his door. I'd love to know what he drilled, and if that worked. My main guess is to see if I can break the unit apart while in the door (I was lucky in that I hadn't put on the door panel yet), and somehow smash it to the point where I can reach up in there and unlock the mechanism from the inside.

But the auto-locks work perfectly.

Any suggestions would be appreciated.

Okay, well the door is still stuck, but I have a few more things to share. Hopefully someone will read this and not make the same mistakes I've made. As I said before, replacing the motors is fairly easy and works well. Scott is to be commended for starting this thread. Add this bit of data to your project and you'll hopefully have no troubles.


First off, here is the missing photo Scott forgot to add. This is the manual locking rod that runs through the lever on the actuator.
This shot was taken up through the driver's side door, so it will be reversed from Scott's photos. You can clearly see the metal pin from the door handle going straight down, and passing through the metal lever on the door actuator. The black box to the right of the pin is the door actuator. This should help you while you're reaching inside the door, and when you put the actuator back.

Now onto where I screwed up. I bought a second door actuator and carefully took it apart, making notes and lots of photos. It turns out the actuator has a few parts that need to be put back in the right order to work. Its not hard to see them once you know what you're looking for. Hopefully these photos will make it clear. I took some form several different angles.

What you need to watch out for it a white pin that is part of the locking mechanism, and a metal blade that is on the end of the arm of the latching mechanism. In Scott's 6th photo you can see the cables that attach to these two parts. The blue ended cable attaches to the locking mechanism, and the yellow ended cable to the latching mechanism. Both of these two pieces, working together, are what unlatches the door so it will open.

This is what you will see when you first start to open the actuator, after you have removed all the screws and popped the little clips.
The actual latch (the part that holds the door closed) has been removed so you can see the parts better.

Heres another photo, open a little more:


When you open it up, this is what you should see on the inside top. These are the two parts I'm talking about:


Here's is where the white pin and the door latch blade need to go when you close it up again.


Same thing, but a different angle:


As you can guess from the above photos all these parts push against a pointed lever on the door latch which causes it to rotate and open the door. Here is a couple of photos of that lever. In this first one its the pointed piece pointing straight up:


Another view, this one from the side. I put a screwdriver pointing at the lever because its hard to see from this angle:




And yet another, here my finger it pointing to the lever as its installed in the actuator:



So follow these directions, making sure the white pin and the blade go in the correct places, and it should work fine.

Now to test your actuator. Fortunately, this part is very easy.

First take a look at the latch part of the actuator assembly. This is the part that holds the door closed. If you look inside the opening in the shiny metal plate you will see a "C" shaped piece of metal that rotates to latch the door. When the door is open, this piece is turned so the open part of the "C" can slide onto the pin on the frame of the car. As this "C" shaped part strikes the pin, it rotates around until the opening is straight down, thus locking the door in place.

Look at these two photos, and play with your actuator until this makes sense.

Here the door is open with the opening of the "C" shaped part to the inside of the door. The opening of the "C" is partially up behind the shiny metal plate, but it is still there.



Here the door is latched, with the opening of the "C" shaped part facing down.


So now, to test your actuator. See the metal lever in the second photo? The one my finger is resting on? All you have to do is first rotate the "C" shaped piece (use a finger or a small tool) until it is in the latched position (like the second photo). Once rotated it should lock, and not move. Now pull down on the lever. If your actuator was assembled properly, the "C" shaped piece should snap back to the open position in the first photo. If it doesn't, DO NOT INSTALL IT IN YOUR CAR.

See, simple.

If you have any questions, please feel free to ask.