You can use the sound system or MMI* to set, alter or cancel the speed limit warning.
Vehicles with sound system
Select: SETUP button > control button
Driver assist > Speed warning.
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Vehicles with MMI
Select: MENU button > Car > control button Systems* > Driver assist > Speed warning.
The speed limit warning can be adjusted in increments of 10 km/h between 30 and 240 km/h.