Strange door lock issue

[clash0901]

Hello!

My 91 LC is having a strange issue with the door locks.

None of them will lock or unlock with the actuators. When using the key OR the master switch I can hear all of the actuators working but none of the doors actually lock or unlock.

I haven’t removed the door cards yet to check because they are old and I’m afraid I’ll break something that is not fixable easily.

Before I dig into every single door, does anyone have any theories or suggestions?

I can only unlock each door with a key or manually from the inside.

Thanks

 

[Brindleboxer]

Here are two other posts about the door lock issues;

80 series door lock actuator fix the easy way for the noob.

80 series door lock actuator fix the easy way for the noob. / i didn't find any good info on this and the one video i did find i thought sucked because it left out steps. also i accidentally ordered left side actuator instead of right side somehow (or they mixed up) so i had done extra time and...

forum.ih8mud.com

Door locks not working and I am going crazy

forum.ih8mud.com

There are more but hopefully these two help you out.

 

[clash0901]

Here are two other posts about the door lock issues;

80 series door lock actuator fix the easy way for the noob.

80 series door lock actuator fix the easy way for the noob. / i didn't find any good info on this and the one video i did find i thought sucked because it left out steps. also i accidentally ordered left side actuator instead of right side somehow (or they mixed up) so i had done extra time and...

forum.ih8mud.com

Door locks not working and I am going crazy

forum.ih8mud.com

There are more but hopefully these two help you out.

I appreciate that but I read both of those before making my post and neither are the same issue as mine.

I read quite a few actually and didn’t find a single one the same as mine.

Thanks

 

[Irish Reiver]

On my last '96, I had a similar problem with 3 of the door lock actuators. The problem is internal to the actuator. My memory is sketchy on the details but I seem to recall a plastic arm that is attached to the motor that had cracked allowing the motor armature to spin with out moving the plastic arm.
There are a few write ups about the fix on the site if you search. I remember I was able to fix my passenger door but ended up buying new actuators for the rears.

 

[DivByZero]

Note that the problem with the plastic breaking was rectified with later year models. They did a revision where they made the inner metal post smaller and the locking plastic ring thicker, which doesn't seem to break the way the earlier design does.

 

[clash0901]

On my last '96, I had a similar problem with 3 of the door lock actuators. The problem is internal to the actuator. My memory is sketchy on the details but I seem to recall a plastic arm that is attached to the motor that had cracked allowing the motor armature to spin with out moving the plastic arm.
There are a few write ups about the fix on the site if you search. I remember I was able to fix my passenger door but ended up buying new actuators for the rears.

Yea I’m trying to avoid taking all 4 door cards off but I think that’s going to be necessary. That was also one of my guesses, the plastic clips holding the arms are broken. Just odd that it happened to all 4 doors.