Tire tread
WARNING
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the tread wear indicators (TWI) become
visible at approximately 1/16 in (1.6 mm), we recommend that you do not allow
your tires
to wear down to that level. As tread depth
approaches 1/8 in (3 mm), the adhesion
properties on a wet road are sharply reduced.
Depending upon the weather and/or road surface (conditions), the tire traction varies widely.
Do not use tires that are excessively worn as the tire traction on wet road surfaces decreases significantly when the tread depth is less than 1/8 inch (3 mm).
Tread wear indicators (TWI) are required by law. Six indicators are positioned on the tire tread. They become visible as soon as a tread depth of approximately 1/16 inch (1.6 mm) has been reached. If this is the case, the tire is so worn that it must be replaced.
The recommended tread depth for summer tires is at least 1/8 inch (3 mm). The recommended tread depth for winter tires is at least 1/6 inch (4 mm).

Bar marking 1 for tread wear is integrated into the tire tread.
See also:
Safety systems
Display messages
Possible causes/consequences and
Solutions
Risk of accidentABS (Anti-lock Braking System), ESP®
(Electronic Stability Program), BAS (Brake Assist), ...
Problems with the seat ventilation
If one or all of the indicator lamps in the seat
ventilation button are flashing, the seat
ventilation has switched off automatically.
The vehicle's electrical system voltage is too
low because ...
Information for customers in California
Under California law you may be entitled to a
replacement of your vehicle or a refund of the
purchase price or lease price, if after a
reasonable number of repair attempts
Mercedes-Benz USA, L ...
