Mercedes-Benz GLC : Vehicles with Parking Assist PARKTRONIC / System failure
If the rear view camera is not operational, the
following display appears in the multimedia system.

The following camera views are available in the
multimedia system:
Normal view
Yellow lanes marking the course
the tires
will take with the current steering angle
(dynamic)
Yellow guide line, vehicle
width (driven surface)
depending on the current steering
angle (dynamic)
Red guide line at a distance of
approximately
1...
The rear view camera will not function or will
only partially function in the following situations:
The tailgate is open.
There is heavy rain, snow or fog...
Other information:
This is data regarding the operation of the vehicle,
which have been processed by control units.
This includes the following data, for example:
Vehicle status information such as the speed,
longitudinal acceleration, lateral acceleration,
number of wheel revolutions or the fastened
seat belts display
Ambient conditions, such as temperature,
rain sensor or distance sensor
Generally, the use of these data is temporary;
they will not be stored beyond the period of
operation and will only be processed within the
vehicle itself...
..