Tire tread
WARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that on wet road surfaces, the risk of hydroplaning increases, in particular where speed is not adapted to suit the driving conditions. There is a risk of accident.
If the tire pressure is too high or too low, tires may exhibit different levels of wear at different locations on the tire tread. Thus, you should regularly check the tread depth and the condition of the tread across the entire width of all tires.
Minimum tire tread depth for:
• Summer tires: 
in (3 mm)
• M+S tires: 
in (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached.
Bar indicator 1 for tread wear is integrated into the tire tread.
Treadwear indicators (TWI) are required by
law. Six indicators are positioned on the tire
tread. They are visible once the tread depth
is approximately 
in (1.6 mm). If
this is the
case, the tire is so worn that it must be
replaced.
See also:
HOLD function
Important safety notes
WARNING
When leaving the vehicle, it can still roll away
despite being braked by the HOLD function if:
• there is a malfunction in the system or in
the voltage supply.
• t ...
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