Trying to repair the non operational driver's side door key hole on my 92 400E. The problem is, you put the key in and it just turns in a full circle, feels like no mechanism is being engaged. The door can be locked from passenger side or trunk. Has anyone experianced this problem? If so was it difficult to repair?

Any info would be greatly appreciated?

Good Morning

If you’re lucky the roll pin that secures the rod to the tumbler is the only problem, you will need to remove the door tumbler for further investigation. If the lock is rotating 360 degrees then you may have a tumbler problem as well.

Open door, 90 degrees from the tumbler on the face above the latch mechanism you will find a cap and an oval trim piece. Remove both trim pieces and disconnect the electrical connector (secure the clear connector so it does not fall into the door). Carefully remove the 3mm allen screw (seen through the round hole), loosen the screw but only to the point where the tumbler slips away from the door. If you are not careful you could drop the screw inside the door!

You should be able to figure out the rest from there

FYI: When you install the tumbler with the rod attached insert the key and rotate tumbler in order for the rod to seat in the lock/latch.

Excelent instructions! I fixed it in less than 10 minutes. Can't belive the dealer wanted $195 to do that. Thanks so much for the great advice.

You're welcome!

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