Mercedes-Benz Zetros 2020 Operating Instructions Manual page 136

Trailers/semitrailers
134
Arrangement of connections
Example: connections for semitrailers
Example: connections for trailers
Connecting cables and compressed-air
lines
! Arrange the cables and compressed-air
lines in such a way that they easily yield to
all movements without tension, kinking or
friction when cornering, etc. Before con-
necting the cable, make sure the voltage
rating of the consumer equipment on the
trailer is correct.
If you connect a trailer/semitrailer to the vehi-
cle's 12 V electrical system, use an appropri-
ate voltage transformer. You can obtain a volt-
age transformer from any Mercedes-Benz Ser-
vice Centre.
X
Connect brake line coupling head : (yel-
low).
X
Connect reservoir line coupling head ;
(red).
i The shutoff valves in the coupling heads
open automatically when the connection is
made.
X
After connecting the compressed-air lines to
the trailer/semitrailer, adjust the brake-
pressure regulator (if installed).
X
Connect the voltage supply to the socket or
to 24 V (15‑pin) plug ?.
X
Connect the connecting cable to the socket
or to ABS/BS (5/7-pin) plug =.
X
Semitrailer tractor vehicles with ABS: if the
semitrailer tractor vehicle is being driven
with a semitrailer without ABS, insert the
connection cable into empty socket A.
X
Check lighting systems, turn signals and
brake lamps on the vehicle and on the
trailer/semitrailer for correct functioning
and cleanliness.
X
Check the operation of the indicator lamps
for the tractor and trailer/semitrailer turn
signals in the instrument cluster.
X
After pulling away, check that the brake cir-
cuit on the trailer/semitrailer is functioning
correctly, paying attention to the road and
traffic conditions.
Disconnecting cables and compressed-
air lines
G
WARNING
If you remove the coupling heads in the
wrong order, the trailer/semitrailer brake is
released and the trailer/semitrailer may roll
away. There is a risk of an accident.
Always detach the coupling heads in the cor-
rect order.
! After disconnecting the compressed-air
lines, ensure that the covers of the coupling
heads on the vehicle are closed. If the cov-
ers are not closed, the coupling heads may
become contaminated, causing a malfunc-
tion.
X
Apply the parking brake of the tractor vehi-
cle.
X
Apply the parking brake of the trailer/semi-
trailer. Observe the manufacturer's operat-
ing instructions.
X
Detach reservoir line coupling head ;
(red).
The brakes of the trailer/semitrailer will be
applied automatically.
X
Detach brake line coupling head : (yellow).