Observe the notes on auxiliary heating More.

The hot-water auxiliary heater complements your vehicle's climate control system and has a heater booster, auxiliary heating and auxiliary ventilation function. In addition, the auxiliary heating system heats the engine coolant to protect the engine and save fuel during the warming-up phase. The stationary heater heats the air in the vehicle interior to the set temperature. It is not dependent on the heat output of the running engine.

The auxiliary heating is operated directly using the vehicle's fuel. For this reason, the fuel tank must have been filled above the reserve fuel level so that the auxiliary heating can work.

The stationary heater automatically adjusts its operating mode to changes in outside temperature and weather conditions. It is therefore possible that the auxiliary heating may switch from ventilation to heating mode or from heating to ventilation mode.

When the engine is running, auxiliary ventilation is not active. Auxiliary heating will automatically switch itself off after a maximum of 50 minutes. You cannot use the "Stationary ventilation" mode to cool the air in the vehicle interior to a temperature lower than the outside temperature. Auxiliary heating helps to heat up the vehicle while the engine is running and at low outside temperatures.

You can set up to three departure times for pre-entry climate control by remote control or via the multimedia system. The switch-on time is then calculated based on the outside temperature and the activated departure time. This means that your vehicle is preheated or precooled by the set departure time.

If the departure time is reached and the engine is not started, the auxiliary heating will continue to run for approximately five more minutes. It will then switch off automatically.

When the auxiliary heating system is operating and the engine is started at the end of the remaining time, the heater booster function of the auxiliary heating system will be activated.

If the auxiliary heating is ventilating and the engine is started at the end of the remaining time, the auxiliary heating will switch off automatically.