Yes, it is the battery heater coolant heater. Really disapointed with Tesla service.
See here my story :
Took delivery of our second Tesla, service was miserable.
The new model s performance came with no charge cable for three phase so we cannot charge it at home.
When we took delivery 5 years ago of our P85D, it came with all adapter and a nice leather keyring, etc. The summum feature is now a 7500€ option whereas it was standard in the P85D !
The new car works fine but after returning home, the P85D showed 2 error code and the power was reduced.
According to Tesla, after had all difficulties in the world to call them, it seems to be the heater battery system which is in fault.
The car is not under guarantee since 2 months, it has only 30k miles on it. Tesla is not able to loan us a car while it’s in repair so we have to rent a car by ourself.
We have to tow the car to the SC (250km).
Poor service, not even a single commercial gesture after buying 2x 110k€ car, had all difficulties in the world to reach someone in the phone.
Really disappointed with the Tesla service.
Better to have failure with a Renault, at least you can have a car in replacement.