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Hi all,

I'm picking up my M3P on 9th December and have a question. If I'm in the house and use the app to turn on the heating (car plugged in to wall charger), does this also warm the battery? Also, does the power from the heating by default come from the charger, or from the battery? If from the battery, once it has dropped a little in SOC, will it automatically start charging to bring the SOC back to the predetermined level?

Cheers all,

Paul
 
I'm not sure whether it also warms the battery, I just assumed it did. The power comes from the battery, and once it is finished charging a new charging session does not automatically start after the SoC has been reduced.
 
Hi all,

I'm picking up my M3P on 9th December and have a question. If I'm in the house and use the app to turn on the heating (car plugged in to wall charger), does this also warm the battery? Also, does the power from the heating by default come from the charger, or from the battery? If from the battery, once it has dropped a little in SOC, will it automatically start charging to bring the SOC back to the predetermined level?

Cheers all,

Paul
M3 does not have a separate battery heater like MS and MX but does use the HVAC for that purpose, so yes it will warm the battery if needed. Power always comes from the battery and if drain reduces battery by more than 3% the car does start charging back to set level
 
The power comes from the battery,

Power always comes from the battery

While technically “correct” (the wall connector charges the battery which runs everything else) when you turn on cabin preheating, the wall connector or UMC will turn on and as much power as possible will be drawn from that source. Anything that cannot be supplied from that is drawn from the battery resulting in loss of charge. As I said, technically everything is drawing from the battery. But if the demand is low enough, the wall connector supplies all the current to the battery which is then used to preheat the car, and the battery will not discharge.

It is not required that the state of charge drop for the wall connector to start providing current.
 
While technically “correct” (the wall connector charges the battery which runs everything else) when you turn on cabin preheating, the wall connector or UMC will turn on and as much power as possible will be drawn from that source. Anything that cannot be supplied from that is drawn from the battery resulting in loss of charge. As I said, technically everything is drawing from the battery. But if the demand is low enough, the wall connector supplies all the current to the battery which is then used to preheat the car, and the battery will not discharge.

It is not required that the state of charge drop for the wall connector to start providing current.
I just found out that the wall charger starts charging again when input on defrost, but you came in here before me.
 
M3 does not have a separate battery heater like MS and MX but does use the HVAC for that purpose,
No, it doesn't use the cabin HVAC for that. The car has the coolant loop to be able to gather excess waste heat from the motor. So it uses a system of running current through part of the motor system while the car is not moving to intentionally generate waste heat there, and then it can gather that to send through the battery pack.
 
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