Same for the Zoe. It is interesting to consider how to make "brake by wire" safe. Stop and consider it a second... (Answer:) The pedal has failsafe interlock

Same for the Zoe. It is interesting to consider how to make "brake by wire" safe. Stop and consider it a second... (Answer:) The pedal has failsafe interlock between your foot and the master cylinder which is "normally closed". When you ask for braking and the computer is running right, and the propulsion system can regen, then the brake pads will receive zero hydraulic pressure. If anything keeps regen from working (computer or network failure, batter is full, you are asking for more braking than the motor can make), the failsafe kicks in and your foot is connected straight to the master cylinder in order to make as much hydraulic pressure at the pads as you care to make.