Q: Q: Ignition key will not turn

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the car was operating fine one day and then the next morning the ignition key would not turn.

My car has 155000 miles.
My car has an automatic transmission.

The simplest answer would be that the wheels are turned sharply and there is pressure on the column lock preventing the actuator from moving.You should be able to move the steering wheel slightly in one direction or the other. Give the wheel a little pull in the direction that you can move it and hold it there while you insert the key. If the actuator then moves,(you can hear it when you put the key in the switch) then you’re in business. Another possibility is that the battery is dead so the Electronic Ignition Switch (EIS) is inoperative. There are a few other reasons why the EIS may not be recognizing the key but the solutions for these would involve using the Mercedes Diagnostic Equipment. If you find that you need help with this, you can contact Your Mechanic to have a technician come to your home or office to diagnose your Mercedes and let you know what it will take to solve your problem.

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