sarhoshamiral

Is there a way to pre-heat the car using power from the charger? I usually keep the car plugged in with 80% charge level but in cold weather (30-40F), I noticed that preheating still consumes battery and I will start my trip at around 78%. I usually toggle preheating ~10 minutes or so, should I turn it on even earlier?

finlayson

All power to the car's systems will come from the (high-voltage) battery (or from the 12V battery, which is kept charged by the high-voltage battery). I don't know of any EV that uses power from the external charger to do anything other than charge the battery. And that probably wouldn't make much sense anyway; the extra complexity wouldn't be worthwhile.

But perhaps the car's charging system could be a little smarter, so that it doesn't just stop charging at 80% (or whatever level you've set), but instead resume charging should the charge level drop below 80% later (e.g., due to electricity being consumed for preheating the interior). This might just be a simple software update (but unfortunately, nobody from Mercedes-Benz engineering reads this forum :-)

QuadBenz

Can you set the car to 90% while it's preheating so that it starts charging?

icwhatudidthere

I’ve got an EQE and it’s always charging whenever I turn on preheating. I plug it in at night, it finishes charging sometime around 3am but when I get to the car in the morning, I find the charge indicator is blue. This only happens when I have it set to preheat. Otherwise the light is off and charger is unlocked.

That said, it still shows as 79% so it’s still not enough to cover the charge used.

LAZARU5

Based upon what icwhatudidthere reports above, it may be necessary to change the charging level from 80% to 90% thirty minutes before departure to balance the power used when you start to preheat the car ten minutes before departure.