See also:

BAS PLUS (Brake Assist System Plus)
BAS PLUS is only available in vehicles equipped with DISTRONIC PLUS. Observe the "Important safety notes" section. At speeds above approximately 20 mph (30 km/h), BAS PLUS assists ...

Cleaning the seat belts
– Use clean, lukewarm water and soap solution. Do not clean the seat belts using chemical cleaning agents. Do not dry the seat belts by warming them above 176 °F (80 °C) or placing them ...

Conditions for activation
RACE START can be activated when:  - the doors are closed.  - the engine is running and it has reached an operating temperature of approximately 176  °F (80 °C). This is the case ...