Easy Rider, even though the car is off the electric brake booster is always active, according to my understanding. As a result every time the brakes are applied by the portable braking system the brake booster will engage and drain the battery.
The braking system is boosted hydraulic. If you lose the electric boost pump the brakes are still hydraulic but have a very hard pedal application to stop, just like a conventional ICE. Except with the FFH, the initial gentle braking is done with the battery regeneration system. Unless the brakes are used in an emergency, then it's a full caliper operation, along with regeneration. The boost pump is not operational when the ignition switch is off. You can pump the brakes with the ignition off and the pump never comes on. Turn the ignition on and the boost pump starts immediately.
Edited by gkinla, 21 October 2014 - 01:48 PM.