Door lock motor failure-confirmed (1 Viewer)

[NLXTACY]

Finally got tired of the stupid rear door locks. They are the only ones that have been an issue. They either work half way or not at all. So I finally broke down and tore apart the 2nd row door by taking off the entire panel. Not a big deal. Getting to door lock motor was a little more of a challenge to figure out since the FSM didn't give the info I was looking for. No worries. I pulled back the upper right corner of the vapor barrier and got access to the door lock plug. Quick check on the connector showed that there was about 11v going to it to unlock, then swaps the pinouts to unlock it. 11v on that direction to. Ok so its getting power. I brought in 12v (pos/neg) to test the door lock motor connector. It barely moves in one direction and not at all the other direction. So out it came. You have to disconnect the linkage to the door handle and unscrew the three screws to the door lock itself, the piece with the child safety lock. It all comes out in one piece as you can see.

My first step was to unscrew the 5 gold screws holding down the motor and the gearing. I was determined to repair this bad boy. When I took off the cover I could see just how basic it was. A simple 12v magnetic coil-wound motor and a simple gear. That's it.

 

[NLXTACY]

So back into the garage to supply 12v to see where the issue is. 12v straight to the motor connector and nothing. I switched polarity and I get a small bump but that's it. I thought that maybe there was a problem with linkage or gearing and maybe something broke. So I took out the motor (it pulls right out with zero effort) and went back to test the motor by itself without any linkage nor gearing. Nothing. Switch polarity and I would get a little bit of spinning but it was super weak and it lasted maybe four revolutions. Ok bad motor. Time to tear it apart.

 

[NLXTACY]

Lifted up the two lock tabs on the motor housing and slipped off the connector from the housing itself. LOTS of junk inside. The first photo is after I knocked out all of the material that built up. I cleaned the whole housing connector up. Continuity checks showing everything was good. For kicks I brought it 12v and with the multimeter I got good 12v to the connector blades that rotate along t he bottom of the coil shaft. All good there. So there was one last culprit, the magnets. The air gap is most likely out of spec. I can't find anything useable online but this seems to be the culprit. Too much material has been worn away so there is no good magnetic operation. I "could" just replace the magnets but I would need to hunt down the correct size with the correct radius and then trim it down to fit. More of a pain in the ass than I want to get into. I am just going to order up some new motors.

If you are curious and want to learn more about these motors go here: http://en.wikipedia.org/wiki/Brushed_DC_electric_motor

Solution: buy new door lock motors.
Passenger rear part number: 69130-60010 (~$80)
Driver rear part number: 69140-60010 (~$80)

 

[greentruck]

Interesting. Great documentation!

Our 80 sometimes tries to lock, but only makes a noise that sounds like half the effort that it takes to actually make them work when it does lock. This results in everything staying unlocked, then I bump the remote button again and then it locks properly with a positive sound.

Was your symptom just with the door with the bad actuator? Or does it provide system feedback somehow and all the locks stay unlocked if one fails to lock?

 

[NLXTACY]

Without fail the front doors and hatch locks just fine without issue. For years the 2nd row got progressively worse to the point where they don't do anything, at all.

I do not have the remote door keyfob so...

 

[hobbes]

My locks, starting with the rear, got lazy and finally stopped working. I pulled them out and took the motor apart as above. As a no-talent hack it was easy, even for me. No problems with the magnets. I just cleaned everything up with electrical cleaner and sand paper any place I saw carbon. Lightly greased it and reassembled. The fix has held for two years, even when it gets cold.

 

[Kernal]

Good work: what was the source of the junk you found, and can you post up photos of the magnets and the armature by itself (pulled out of the case)? I went through something like this with a window lift motor, cleaned and regreased, volts and DC amp draw checked out good but it still did not produce enough torque to wind up the window regulator spring.

 

[NLXTACY]

My locks, starting with the rear, got lazy and finally stopped working. I pulled them out and took the motor apart as above. As a no-talent hack it was easy, even for me. No problems with the magnets. I just cleaned everything up with electrical cleaner and sand paper any place I saw carbon. Lightly greased it and reassembled. The fix has held for two years, even when it gets cold.

Literally was doing that before I saw your post just to see what happened after cleaning and re-greasing. I get no change.

 

[NLXTACY]

Good work: what was the source of the junk you found, and can you post up photos of the magnets and the armature?? I went through something like this with a window lift motor, cleaned and regreased, volts and DC amp draw checked out good but it still did not produce enough torque to wind the regulator spring.

The gunk was definitely material from the ferrite magnets, mixed in with the little bit of grease that was at the bottom of the axis. I want to remove the entire armature and coil but it would mean cutting off the spiral gear. Guess I can being as its just now. I bet if I put some shim material onto the magnets it would work fine. Hmm.....

 

[NLXTACY]

Found a good video online, presumably by someone here on MUD:
http://www.youtube.com/watch?v=Td2vwnA9iOk

 

[Kernal]

Was the armature rubbing against the magnets? If so are the armature bushings worn out of spec allowing the armature to wobble or could the magnets have come loose (they don't look loose in the photos)? So cleaning the motor up and putting it back together didn't help?

FWIW when I pulled my slow windshield wiper motor apart I found that one magnet had popped loose from the case causing it to get pulled onto the armature which then ground material off that magnet.

 

[NLXTACY]

Was the armature rubbing against the magnets? If so are the armature bushings worn out of spec allowing the armature to wobble or could the magnets have come loose (they don't look loose in the photos)?

FWIW when I pulled my slow windshield wiper motor apart I found that one magnet had popped loose from the case causing it to get pulled onto the armature which then ground material off that magnet.

Magnets aren't moving. I haven't tried prying them off yet. There is nothing that leads me to the conclusion that it was wobbling. Could be but I see no evidence of it.

 

[Kernal]

So after cleaning the motor it still doesn't move?

 

[NLXTACY]

So after cleaning the motor it still doesn't move?

Negative on one polarity and very little (4-5 very slow revolutions) on the other.

 

[Kernal]

With a bright light can you look inside the case and see the face of the magnets, do they appear to have wear grooves from contact with the armature?

 

[blkprj80]

Inside the motor, toward the top in the pic showing the brushes, is that a thermal cutout? Post #3, pic #3.

Sometimes they use thermal cutouts on these motors to prevent someone from leaning on the switch and burning something up. The thermal cutouts are usually what burns up... If you bypass it, it might make it go.

Excellent writeup NLXTACY. Thanks for digging in and sharing the carcass with the rest of the pack.

 

[NLXTACY]

With a bright light can you look inside the case and see the face of the magnets, do they appear to have wear grooves from contact with the armature?

Yeah been there. Nothing obvious.

 

[Kernal]

Inside the motor, toward the top in the pic showing the brushes, is that a thermal cutout? Post #3, pic #3.

NLXTACY: can you post up a better photo of that area?

 

[NLXTACY]

SOR has both the left and right and they are $50 ea. I called my local Toyota dealership and they want $150. Ugh. I'm going to test the used ones really quick with the battery and go to town.

 

[Mr Cimarron]

I have the same problem with my PS rear door. Takes 3 clicks to unlock or lock the door. I meant to get the part from a pick n pull but forgot my list when I went so I forgot. Does anyone know if other toyotas share the motor since LCs are rare at pick n pulls.