The present invention also pertains to a coupling head (10, 100, 200) for a trailer, the coupling head comprising a control inlet (16, 106. 206) connected or connectable to be in fluid communication with a control line (44) of the trailer, a supply inlet (14, 104, 204) connected or connectable to a supply inlet line (13) providing a supply pressure, and a supply outlet (34, 138, 224) connected or connectable to be in fluid communication with a supply line (36) of the trailer. The coupling head (10, 100, 200) is arranged such that in an uncoupled state of the coupling head, the control line (44) is exhausted via the control inlet (16, 106. 206) and the supply line (36) is exhausted via a supply exhaust (32, 146, 244), the supply exhaust (32, 146, 244) being sealed against the control inlet (16, 106, 206). The invention also refers to a trailer with such a coupling head (10, 100, 200).
