Powered up, the key transponder sends the key identification code to the transmitter/receiver module via the 125kHz AM signal. The transmitter/receiver module converts the AM signal to a digital signal and sends it to the EWS.
The EWS control module verifies the key identification code and checks to see if the key is enabled.
Upon accepting the key as valid and enabled the EWS sends a digital password to the transmitter/receiver module, which converts the data to an AM signal and sends it to the transponder via the induction ring.
If the transponder accepts the password as correct the transponder releases the changing code to the transmitter/receiver module which converts this AM signal to digital and sends it to the EWS.
If the changing code received by the EWS is correct, and with correct input status the internal starter relay is energized and the starter motor begins to operate. At the same time the EWS module sends the ISN to the DME via the single wire communication link.
If the ISN code stored in the EWS matches that of the DME, the drive away protection is cancelled, the injection and ignition is enabled.
During the process of sending the ISN to the DME, the EWS sends a new changing code to the transponder through the transmitter/receiver and ring antenna.
This all happens within 750ms !