A charging line can be established via contact number 10 of the 13-pin connector according to ISO 11446. This contact is primarily used to charge a battery in the trailer (for example to supply appliances in a caravan).
The charging line is connected to the battery via a cut-off relay as soon as the ignition is started or the engine is running.
The connecting cable to contact number 10 and the respective common return lead to contact number 11 should have a diameter of 2.5 mm² and a fuse protection of 20 A at most.
Advice:
According to the ISO 11446 standard, the common return contacts number 3, 11, and 13 must not be connected electrically conductive.