So I had the unfortunate experience of having two tumblers fail in under a year.

The first one, I caught it soon enough and was able to remove it gracefully by having it in key position "1", and it was replaced under warranty.

The replacement unit, now with only 1-month of pro-rated warranty left, failed in 9-months, and we run at most 3-keys on the ring, so no undue weight here.

Unfortunately, the failed tumbler would not turn into position "1", so this meant drastic measures had to be taken.

I was able to "break" the tumbler and turn it into position "1", but couldn't get it to release.

There was no way I was going to try and cut though the black protective ring.

So what to do:

1) remove lower dash trim on steering wheel side to reveal the ignition lock.;
2) remove the steering wheel and airbag, if any (remember to disconnect both the battery and the "red" airbag connector under the passenger carpet;
3) remove the four allen bolts that hold the steering column to the dash;
4) loosen the single allen bolt that clamps the ignition lock assembly to the steering column;
5) disconnect the anti-shifting cable (if any);
6) disconnect rear switch connector;
7) rotate the ignition lock assembly so you can see the hardened pin;

Now you have TWO options:
1 ) if you have a pin-point torch, heat ONLY the pin until it is "red-hot" and let it cool (do not quench it cool, you want to remove the "hardening");
now hit the pin hard with a hammer and punch and remove the ignition lock assembly.

OR

2) with a forged punch and hammer hit the area AROUND the pin until the pin is free to depress/move, and you'll be able to remove the ignition lock (similar to smashing the door and door-frame instead of the deadbolt).

I tried option #1, but with a butane torch I couldn't get the pin hot-enough;

Option #2 worked like a charm!

BTW: the new ignition locks do NOT have their threads tapped for the switch assembly, so you MUST tap them yourself (the dealer said to use self-tapping screws, but not for me!). Stuff a rag into the underside of the ignition lock assembly when tapping and use a little cutting oil to keep the debris from falling into the assembly.

Good luck,

:-) neil
1988 E36T AMG
1993 500E

PS: order a spare tumbler (they need your VIN#, license, and registration) and KEEP it in a safe & accessible place (they usually take 2-3 business days to get).

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