The parking heater is a high-voltage heater. It starts automatically if the parking climate's preconditioning is activated and the passenger compartment needs to be heated up.
It switches off automatically when the car is started.
Battery and charging
The heater is powered by the car's high voltage battery. If the charge level of the high voltage battery is too low, then the heater is switched off automatically and the driver display shows a message.
Make sure that there is enough charge in the high voltage battery if the parking heater needs to be used.