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Electrical system
Trailer detector control unit J345
This ensures that the trailer's electrical components are integrated into the vehicle network.
Location
The trailer detector control unit is located behind the
luggage compartment trim on the left-hand
side panel.
Tasks
The trailer detector control unit determines
whether a trailer is connected to the trailer socket,
and makes this information available to other control
units via the CAN data bus.
It controls the trailer's lighting and also diagnoses the
functional capability of the majority of trailer bulbs.
As a CAN subscriber, it reads all messages required
for trailer operation, e.g. for the reversing light or turn
signals, and processes these to actuate the trailer's
corresponding lighting components.
This also applies to equipment-dependent
convenience electronics functions such as automatic
headlight control or the Coming-Home lighting and
safety functions such as the hazard warning lights in
the event of emergency braking.
Trailer detector
control unit J345
Trailer socket
Left turn signal
Right turn signal
Left side light
and brake light
Right side light and
brake light
S338_104
S338_109
