I am the owner of an ’09 MMH, and have a question on battery charging. I understand that the 12V (under hood) battery is used to power accessories, and to close the contacts to the HV battery, which spins the electric motor, which starts the ICE. That means that the HV battery must have sufficient charge to start the ICE. If the car stands idle for a long period, the manual mentions that the 12V battery will have to be charged or jumped, but is there any way (any need?) to be able to charge the HV battery?
I have read about a switch on older FEH/MMH models to “jump start” the HV battery from the 12V one, but can find no mention of it in the ’09 manual. Is there a way to charge the HV battery after a long period of no activity?