See also:

Direction of rotation
Tires with a specified direction of rotation have additional benefits, e.g. if there is a risk of hydroplaning. You will only gain these benefits if the correct direction of rotation is maintained ...

System self-test
After you have switched on the ignition, the system carries out a self-diagnosis. WARNING   A malfunction in the system has been detected if one of the following conditions occurs: • t ...

High outside temperatures
If DEF heats up to over 122 °F (50 °C ) for extended periods, e.g. as a result of direct sunlight on the DEF reservoir, DEF can decompose. Ammonia vapors develop as a result. WARNING When o ...