If a temperature of approximately 160 °C is exceeded, the driver sees an alarm in the driver's display as well as the message "Engine compartment fire". Additionally, an acoustic warning tone is emitted and the extinguishing process initiated automatically.
In the case of a fire, the pressurised detection line (Firetrace) breaks and sprays an extinguishing mixture made of water, engine coolant and a special additive via a series of nozzles around the entire engine compartment. The water mist evaporates as a result of the high temperatures and displaces the oxygen. The engine compartment is thus cooled rapidly, the fire extinguished immediately and re-ignition of the fire prevented.