Mercedes-Benz E-Class Coupe 2017 Owner's Manual page 399

396 Display messages and warning/indicator lamps
Vehicle
Display messages
j
Trailer coupling extending...
Possible causes/consequences and
* Retract or extend the ball neck.
Do not attempt to speed up, slow down or initiate the retracting or extending process using your hand, foot or other
aids. During the retracting or extending process, do not couple a trailer.
When the ball neck has reached an operational position, the display message disappears.
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