Mercedes-Benz A Series 2015 Owner's Manual page 237

Towing a trailer
234
Pull out release wheel =.
X
Turn release wheel = anti-clockwise as far
X
as it will go.
The ball coupling disengages and folds out
behind the rear bumper. Indicator lamp ?
flashes.
Press the ball coupling in the direction of
X
the arrow until it engages behind the
bumper.
The indicator lamp on the release knob and
the message in the multifunction display go
out.
Trailer power supply
! You can connect accessories to the per-
manent power supply up to a maximum of
240 W.
You cannot charge a trailer battery using
the 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.
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 to position 2 or 0
respectively ( page 157).
Y
Failure check for LEDs
If LED lamps are fitted in the trailer, a mal-
function message may appear in the multi-
function display even if there is no fault. The
reason for the error message may be that the
current has fallen below the minimum of
50 mA.
To ensure reliable operation of the failure
indicator, each LED chain in the trailer lighting
must be guaranteed a minimum current of
50 mA.
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
! Make sure that there is sufficient cable
play so that the cable cannot become
detached when cornering.
! Remove the installed adapter cable
before folding in the ball coupling. Other-
wise, damage may occur to the rear
bumper and the adapter cable.