Electronic Key won't turn in ignition switch. Batteries are new, and work unlocking doors. Is it possible the ignition switch is bad? Is there a fuse for the electronic ignition that could be an issue?
I have same problem on my W211(E270CDi). What I discovered is that if I knock the key against a surface such as the steering wheel the key is then "swallowed up" sweesh by the EIS: 1. Knock the key then try starting/unlocking the steering 2. If the key does not work go back to 1 above until it works. One time I tried it more than 20times before it worked. There seems to be something that when given a shake/shock it response and the key works. The best solution of course is to replace the key.
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