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. If necessary, the engine output is also modified to keep the vehicle on the desired course within physical limits. ESP® assists the driver when pulling away on wet or slippery roads. ESP® can also stabilize the vehicle during braking.

If ESP® intervenes, the ESP® warning lamp flashes in the instrument cluster.

WARNING
Under no circumstances should you deactivate ESP® when the ==  ESP® warning lamp in the instrument cluster flashes. Proceed as follows:
• when driving off, apply as little throttle as possible.
• while driving, ease up on the accelerator pedal.
• adapt your speed to suit the prevailing road and weather conditions.
Failure to observe these guidelines could cause the vehicle to skid. ESP® cannot prevent accidents resulting from excessive speed.

The ignition must be switched off if the vehicle is being towed with the front or rear axle raised. Otherwise, ESP® may intervene and damage the brake system.

Do not tow vehicles with 4MATIC with the front or rear axle raised.

Only use wheels with the recommended tire sizes. Only then will ESP® function properly.