Mercedes-Benz GLK 300 4MATIC 2012 Owner's Manual page 224

Replace the cover of the ball coupling
X
recess and engage it.
Fold the trailer power socket upwards.
X
Trailer power supply
When it leaves the factory, your vehicle's
trailer socket is equipped with a permanent
power supply and a power supply that is
switched on via the ignition lock.
The permanent power supply is supplied via
trailer socket pin 9.
The power supply that is switched on via the
ignition lock is supplied via trailer socket pin
10.
! You can connect accessories with a
power rating of up to 240 W to the perma-
nent power supply and with a power rating
of up to 180 W to the power supply that is
switched on via the ignition lock.
The trailer battery may not be charged from
the power supply.
The trailer's permanent power supply is
switched off in the event of low vehicle supply
voltage and after six hours at the latest.
You can find more information about fitting
the trailer electrics at a qualified specialist
workshop.
To switch the connected power supply
X
on or off: turn the key in the ignition lock
to position 2 or 0 respectively.
Trailer with 7-pin connector
General notes
Trailer with 7-pin connector: you can con-
nect to the 13-pin socket on the ball coupling
using an adapter or, if necessary, an adapter
cable. Both can be obtained at a qualified
specialist workshop.
Fitting the adapter
Open the socket cover.
X
Insert the plug connector with lug : into
X
groove ; on the socket. Turn the connec-
tor clockwise as far as possible.
Let the cover engage.
X
If you are using an adapter cable, secure
X
the cable to the trailer with cable ties.
! Make sure that there is sufficient cable
play so that the cable cannot become
detached when cornering.
Towing a trailer
Z
221