Isn't there a 'jumpstart' button feature on the FEH so that if your 12v drains you can do a charge from the HV battery manually, then start normally?

 

Erich, its the other way around. The HV battery starts the FEH, the switch discharges the 12V battery into the HV battery to jump start the engine. Be careful if you jump start a FEH, you maybe need a jump yourself after it starts if you shut your engine off.

GaryG