See also:

Problems with PARKTRONIC
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Making adjustments in 1 mph (Canada: 1 km/h) increments
Briefly press the cruise control lever to the pressure point, up 1 for a higher speed or down 2 for a lower speed. The last speed stored is increased or reduced. ...

Coupling up a trailer
WARNING Vehicles with air suspension program: While you are coupling or decoupling a trailer, make sure nobody locks or unlocks the vehicle and/or opens or closes doors or the tailgate. The v ...