I need to correct what I said about charging from the brakes causing an over charged battery. After some research in my FEH manuals, I found it is the generator which is slowing down the vehicle in place of the brakes. Brake pedal switches trigger the Transaxle Control Module to use the turning axle as power to turn the generator for charging. This said, the over charge protection is the same as for when the engine is used to charge the battery. The manual said this system is regulated based on the battery level and the need for a charge. I would think that if the longer you keep the battery drained, the longer your brake pads will last.

I did find out in the manual that the D/C to D/C converter takes high voltage D/C current from the generator and converts it to low voltage D/C to charge the 12 volt battery for running the bells and whistles. This takes the place of an alternator on the FEH. It would make sence that the engine would keep running to top off the 12 volt battery or keep the fans running for the rear large battery to cool.