I've had this fault twice, basically the key goes into the EIS module and turns but you can't hear the steering lock release and no dash lights come on. (And the car didn't start) There's a blue square plug on the EIS module if I remove it and refit it with the key in position 2 all the dash lights come on, but the steering lock is still on. This allows the vehicle to communicate with Xentry/star diagnosis but there's no fault codes and I can't find a way of actuating the steering lock. The car still won't start, and if I switch the ignition off I have to go thru the process of disconnecting and connecting that blue plug again.

Ive had the same fault on a A class and B class

really could do with some help, any information would be useful

i checked battery and fuses all ok

 

What model is this in reference to?