MKH wrote: ↑
Tue Jul 07, 2020 1:01 pm
The 12v car outlet isn't powered by the 12v battery like in an ICE car, it is powered by the DC/DC converter, so checking the voltage from the outlet only shows the DC/DC converter voltage.
I think a more precise way to state this is that all 12 V loads and outlets are on the 12 V circuit. Power sources for this circuit include the 12 V battery and output side of the DC-DC converter. The voltage measured anywhere on this circuit, including at the auxiliary power ports, is that of the 12 V battery, ~12.7 V resting voltage for a fully-charged AGM battery, unless the DC-DC converter is on, in which case the 12 V system voltage is that of the output of the DC-DC converter, ~14.3 V. When the high-voltage system is on (e.g., after unlocking or opening a door, the frunk, or the hatch), the DC-DC converter is on. Both the high-voltage and 12 V systems time out and shut off after a period of inactivity.
2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE