How to remove W124 door lock without key? - PeachParts Mercedes-Benz Forum

gsxr · #1 11-25-2009, 11:17 AM

Hi folks,

I tried searching the forum but couldn't find any thread with this information for a W124 chassis:

I need to remove the door handle + lock cylinder from the driver's door on a 124 (300E, 400E etc) without the key. The problem is, the factory procedure (job 72-240, online here) requires the key to be inserted and turned 60°. I've done this many times with a key, but I don't see how it's possible without the key.

For example, if you want to remove the locks from a car at a salvage yard where the key has been lost, and you can't just order a new key from the dealer since you don't own the car. Or you buy a door from a salvage yard, and need to remove the old/existing lock from the door without the key.

Anyone BT, DT? Help!

lorainfurniture · #2 11-25-2009, 11:24 AM

I requires a lot of patience.

Basically, you will have to dismantle a whole bunch of door innards to make it happen.

I Cant remember exactly what I did, but I think you have to remove vacuum plunger, and unscrew the door latch.

Once the door latch is loose, the lock will have enough play to turn the whole unit 60* to remove. It involves turning the latch too..

It took me 2 hours to get it apart, and 30 minutes to get it back together.

gsxr · #3 12-02-2009, 09:00 AM

Eugene, thanks for the info... someone else also mentioned a slightly different method, but apparently it is possible without the key. Either method is a PITA - as you said, it was a 2.5 hour project. Unfortunately, I didn't have time to try either one.

As a last ditch effort, I tried different keys from other W124's. With several in our family, we had keys from a half-dozen different cars to try. I was pushing the key in & out (sawing back + forth) while applying gentle pressure clockwise. The first five keys were dead ends... the lock didn't budge one millimeter. Key #6 did the trick... it turned part way, maybe 30-40° at most. It would not fully turn, but it turned just enough to allow the lock assembly to be removed. In about three minutes, I had the locks swapped out! Bottom line - if you have access to a bunch of different keys for the same chassis... try them all!

Another option (if you don't want to tear the door innards apart) is to beg for assistance at the dealership - after explaining the dilemma to a sympathetic parts or service guy, they should be willing to order the key (which you'd have to pay for, of course) and hopefully let you use it to remove the offending lock, then you let the dealer keep the key (since you don't legally own the vehicle it fits). This only works if you know the VIN of the donor vehicle. Tip: If you bought a used door, the VIN is usually either on the DOT tag on early cars, or on a production label on the back side of the trim panel (if the panel is still on the door). If you removed the door from the donor car, just get the VIN from the tags on the chassis.

Hope this helps someone else in the future!

babymog · #4 12-02-2009, 09:09 AM

I have done this without a key, I removed the bolts securing the latch assembly and gained enough slop to disengage the lock assembly. I also removed the door card to be able to reach in and manipulate the latch assembly. Probably about 20minutes.

vstech · #5 08-29-2012, 06:22 PM

I do wish more details were included in the 20 minute job...