See also:

Folding the seat backrest forward
Folding the seat backrest forward Move the driver's or front-passenger seat forward if necessary. Open the trunk. Pull right-hand or left-hand rear seat backrest release handle 1. The ...

Mercedes-Benz M-Class Owners Manual
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ATTENTION ASSIST Warns Drowsy Drivers
Drowsiness is one of the most common causes of accidents. This is why Mercedes experts have developed the ATTENTION ASSIST system which forms part of the standard equipment of the new Mercedes CL- ...