Hi, My key locks/unlocks doors but won't turn the ignition in my '99 E-320. My wife's key works fine though. Any suggestions? Thanks, John

 

check the key batteries or just go ahead and replace them since it probably needs it anyways. If that doesn't do it then more than likely it's time for a new key..

 

make sure your battery is good if you got a dead battery or not strong enough EIS will not turn

 

Actually, this is not true. The key works through induction and actually requires NO batteries in order to start the car. (Really! Try it!)

It sounds to me like a fractured circuit board inside the key fob. Unfortunately, it's probably time for a new key.

 

try leaving your key in the ignition for a couple hours

 

put the key into the igniton turn it to I or II im not sure and then press the button on the key, once i had this prob, this is how i fixed it, i put in the key turned it and pressen one button after the other for a few seconds, hope this works...it did for me...good luck