See also:

Treadwear indicators
Narrow bars (tread wear bars) that are distributed over the tire tread. If the tire tread is level with the bars, the wear limit of 1/16 in (1.6 mm) has been reached. ...

2011 Mercedes-Benz S-Class Review
Even as BMW, Audi and Jaguar throw new cars into the luxury-flagship ring, Mercedes-Benz has kept its S-Class sedan competitive, with sedans that start below $90,000 and top out at more than double ...

System self-test
If an adult occupant is properly sitting on the passenger seat and the OCS classifies the occupant as an adult, the indicator lamp illuminates and goes out again after approximately 6 seconds ...