Mercedes-Benz R-Class 2012 Owners Manual - Manual (Page 188)

Deactivating/activating PARKTRONIC
:
To deactivate/activate PARKTRONIC
;
Indicator lamp
If indicator lamp ; lights up, PARKTRONIC is
deactivated.
i PARKTRONIC is automatically activated
when you turn the SmartKey to position 2
in the ignition lock.
Trailer towing
PARKTRONIC is deactivated for the rear area
when you establish an electrical connection
between your vehicle and a trailer.
! Remove the detachable ball coupling if
the trailer tow hitch is not required.
PARKTRONIC measures the minimum
detection range to an obstacle from the
bumper, not the ball coupling.
186
Driving systems
Driving and parking