Switching the hazard warning light system on/off
Press button 
.
. If you operate a turn signal indicator while the hazard warning light system is switched on, only the turn signal lamps on the relevant side of the vehicle will light up.
The hazard warning light system will switch on automatically in the following situations:
The airbag is deployed
The vehicle is heavily braked from a speed of more than 70 km/h to a standstill.
The hazard warning light system will automatically switch off when the vehicle regains a speed of more than 10 km/h after maximum full-stop braking.