See also:

Mercedes-Benz M-Class Owners Manual
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Important safety notes
WARNING Gasoline is highly flammable and poisonous. It burns violently and can cause serious personal injury. Never allow sparks, flames or smoking materials near gasoline. Turn off the engi ...

Using the rear center seat belt
If the left-hand rear seat backrest is folded down and back up again, the rear center seat belt may lock. The seat belt can then not be pulled out. To release the rear center seat belt:pull o ...