when benz said - engineered like no other car in the world - they meant it.

That key tumbler and steering lock are made of safe quality hardened steel. Some members here have posted your similar problem. First things first - try a brand new key from MB by providing title and ownership proof, when your old key wears down the lock fails to work.

If that does not help - then you need a vibratory device to massage key key in the lock - the vibration may set it free to spin to position 2 - at this position the whole tumbler can be removed with key. Get a new tumbler from the dealership cut to your VIN, its about 100 USD.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)