The module (10) has a tractor interface including a tractor controller area network (CAN) interface (14) for connection to a tractor CAN connector of a tractor of a tractor-trailer combination coupled to a trailer (31). A tractor warning-light interface (18) is connected to a tractor warning-light connector (22) of the tractor. A trailer voltage-supply interface (16) is connected to a voltage connector of another trailer (37), and a trailer warning-light interface (44) is connected to a trailer warning-light connector (46). An independent claim is also included for a vehicle comprising a trailer.
