Originally Posted by slk230red

You might try a different key.

I just went through this on my '93 190E I've owned since new. I drove the car to CVS and when I came out the key didn't want to turn....first time this has happened. I gave it a wiggle and it turned. I drove it home and parked it, called my indy parts guy and ordered a new tumbler. It arrived from MB in 2 days. I was able to remove the old one with 2 pieces of coat hanger. Luckily I was still able to turn it to position 1 to remove and replace.

Hope you can get it to turn to position 1.
Good luck.