See also:

Trip computer "From start" or "From reset"
The values in the From Start submenu are calculated from the start of a journey, while the values in the From Reset submenu are calculated from the last time the submenu was reset. Press the ...

Mercedes-Benz M-Class Owners Manual
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Coupling up a trailer
WARNING   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 vehicle's level could change an ...