See also:

Important safety notes
See the "Important safety notes" section If ESP® detects that the vehicle is deviating from the direction desired by the driver, one or more wheels are braked to stabilize the vehicle ...

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 ...

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 ...