See also:

Mercedes-Benz M-Class Owners Manual
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AMG vehicles with rear axle locking differential
Your vehicle is equipped with a self-locking differential on the rear axle. For better protection of the differential on the rear axle, carry out an oil change after a breaking-in phase of 200 ...

Activating/deactivating
- To activate: press the button. The indicator lamp in the button lights up. - To deactivate: press the button. The indicator lamp in the button goes out. The cooling with air dehumid ...