Hey, speaking of EWS antennas, go out and try to start your bike with the antenna unplugged.
If that is true, then if the EWS is unplugged, the pair of leads may need a 120ohm terminating resistor.
From looking at the circuitry in the ECU board, the pair of communication leads to the EWS antenna seem like they might be a CANbus interface. Though separate from the CANbus network on the rest of the bike.
It's a thought anyway
I mean, there are security screws on the EWS, and I think those are separate from the security screws on the ignition switch. So maybe unplugging the EWS and adding a termination resistor will do the trick.