[b.u.ti-ful]

I copied this off of a performance chip site and it makes it sound like the DME has to match up with the key. I guess you'll have to call the dealer.

What is EWS-II? EWS-II is an additional theft-deterrent system that BMW installed in cars beginning in Dec 1994 (12/94). On cars with EWS-II the signal from the key must match up to a signal coming from the EWS-II and DME computers or the car will not start.

How does it work? The key for your BMW has a microchip embedded in it that sends an analog signal to an antenna within the ignition lock on the steering column. The antenna sends the signal to the EWS-II computer. The EWS-II computer then checks with the DME to validate the code. The car can only be started when the DME recognizes the code from the EWS-II computer. The key is simply turned, and by the time the ignition switch is reached, the EWS-II system has finished its processes and identified the electronic coding in the key and 'granted' starting permission.