See also:

Functional readiness of the airbag system
When the ignition is switch on, the warning lamp in the instrument cluster lights up briefly and thereby indicates the operational readiness of the entire airbag system and the belt tensione ...

Tire identification marks
Tire size 255/50 R 19 103 Y 255: nominal width in mm 50: aspect ratio in % R: radial tire code 19: rim diameter in inches 103: load rating, not for ZR tires Y: speed rating, before the R on ZR ...

Following part replacement
The same breaking in procedures should be observed if any of the components mentioned above have to be renewed in the course of the vehicle's operating life. ...