My turn to have that problem. My key can still turn in the ignition but I am not using my car ; waiting for the new part ordered on E-Bay ! First , I phoned the dealer ; with the serial number , the could have me the tumbler with the same key I open my door , trunk etc for $249.00 CAN . Then I asked a guy that a Mercedes scrap yard and he said $100.00 CAN. Finally , went on E-Bay and find one for $31.95 including shipping ! Of course , I opted for E-Bay and I went on Youtube and I now know how to pull out the bad tumbler and put in the new tumbler ! I hope it saves people a lot of money !