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65 miles driven - 40% battery loss - Car says 21% battery use


Oct 10, 2017

I have a 2018 Tesla Model S, 100D.
I have MCU2, and AP3.
So my dash says I've driven 63.4 miles, and used 21.3 kWh since last charge.
However my battery is at 51% and I charged to 90%.

I have TeslaFi logging, and the numbers are accurate.
(Adding one trip that was not in the photo.)
Over 40 hours I drove 68.56 miles.
I used 27.60 kWh of battery.
My battery dropped from 88% to 48%.
I'm missing about 13% of my charge.

I do not pre-condition the car; I leave at different times of day.
I do not leave the kids in the car with the AC on.
I do not remotely turn on the AC before I leave.
I cannot use Cabin Overheat Protection, as I have the Enhanced Security Upgrade.

If this was an ICE car, I'd be checking for gas stains on the driveway.

Where is the extra power going- 15% drain in 40 hours is crazy...


Oct 10, 2017
This is just crazy...

Yesterday I drove for 47 minutes, and used 15.78kW of power over 43 miles.
I was in Parked for 23 hours, 5 minutes, and used 7.36kW of power.
My car used 32% of it's power not to drive.

Assuming that this number is somewhat typical, my car wastes 2.5 MWh of power every year.
(About $400 of power at my night-charging rate.)



Well-Known Member
Mar 10, 2016
Yes, Sentry keeps basically all of the car electronics active to the tune of about 300-350w. It’s a massively inefficient “security” system. I refuse to piss away that much energy and turned it off long ago. I only selectively turn it on now when I want it.

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