W126 drivers lock issue

[glovesave33]

Today I put my key in my drivers side lock and turned it. Much to my surprise it turned completely free and did not unlock the door. It feels as if the tumbler has broken free. It turns completely from 9 o'clock to 3 o'clock with no frictions/tension. All other locks and vacuum systems operates fine. The sticky that was posted in the DIY section that searched posts for door locks point too is no longer a valid page. The other posts I found dealt with vacuum issues or tumblers that would not move at all. Mine moves just fine...too fine!

So, does anyone have any advice on this issue? I want to get some feedback before I take the door and handle apart. Advice? Thanks.

California spec 1085 300sd

[280EZRider]

I agree with you: It sounds like a mechanical problem w/the key lock. The system reverts to completely manual when & if the vaccum fails. Also the fact that you have vaccum in the rest of the locking system tells you the system is OK. A final test you can do before going inside the door panel is to close all doors except the left rear. Then w/the left rear open, push down the finger plunger of the driver side door. If the vaccum system is completely OK, everything will lock.

Not to worry: the door panels are easy to remove.

[Mercedes Guy]

I don't know how similar the the W126 tumblers are to the W201 tumblers, but I had that exact problem with my 190E last year. All of the locks worked fine but when I tried to open the driver's door with the key it would just turn back and forth without unlocking or locking the door. I removed the tumbler from the door and found that the small metal tab at the end of the tumbler that engages with the rest of the locking mechanism had snapped off. I was able to order a new tumbler from the MB dealer using my VIN.

I'm not sure of the similarity of the two tumblers, but the symptoms you described are identical to what I experienced.

[spree17]

Originally Posted by Mercedes Guy

I don't know how similar the the W126 tumblers are to the W201 tumblers, but I had that exact problem with my 190E last year. All of the locks worked fine but when I tried to open the driver's door with the key it would just turn back and forth without unlocking or locking the door. I removed the tumbler from the door and found that the small metal tab at the end of the tumbler that engages with the rest of the locking mechanism had snapped off. I was able to order a new tumbler from the MB dealer using my VIN.

I'm not sure of the similarity of the two tumblers, but the symptoms you described are identical to what I experienced.

I had a very similar problem. I just pulled the lock from the passenger side and switched it with the drivers side for now rather than buying a new lock mechanism. In the future Ive considered just adding a remote keyless lock system for like $40 instead of buying a new tumbler.

[sdpartz]

Originally Posted by spree17

I had a very similar problem. I just pulled the lock from the passenger side and switched it with the drivers side for now rather than buying a new lock mechanism. In the future Ive considered just adding a remote keyless lock system for like $40 instead of buying a new tumbler.

That's exactly what I did when my driver's side lock went bad. It was a 89 300 SE