How is the 12-volt battery charged on the PIP? Is it only charged when the HV system runs, or does it also charge when the traction battery is charging from the wall? I've noticed at start up when the PIP is in EV mode the ICE starts spontaneously on occasion, even with the heat and AC both off. The traction battery has a good charge, so it needs to do this for some reason, but why? Is the 12-volt system running low? I drive almost totally in EV mode, so am I running the 12 volt system down? (TOYOTA some answers please)......and by the way the PIP is a dream EV 99% of the time.