Mercedes-Benz GLC : Display messages and warning/indicator lamps / Warning and indicator lamps
Some systems will perform a self-test when the
ignition is switched on. Some indicator and
warning lamps may briefly light up or flash. This
behavior is non-critical...
Other information:
..
DANGER Risk of fatal injury due to damaged
connecting cables or sockets
You could receive an electric shock if the
connecting cable or the 115 V power socket
is pulled out of the trim or is damaged or
wet.
Use only connecting
cables that are dry
and free of damage...