See also:

Vehicle remote opening
If you have unintentionally locked your vehicle (e.g. the SmartKey is still in the vehicle) and a replacement SmartKey is not available, the vehicle can be opened by a Mercedes-Benz Customer Assis ...

Warning and indicator lamps
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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 recomme ...