APPARATUS AND METHOD FOR DETERMINING A STATUS OF THE TRAILER BRAKE

An apparatus for determining a status of controlling a trailer brake by a parking brake system is disclosed. The parking brake system comprises a parking brake port (21), a trailer control module port (22), a sensor (60) configured to measure a pressure at the parking brake port (21), and a valve arrangement (10, 20) configured to connect or disconnect the trailer control module port (22) and the parking brake port (21) to allow exhausting of the trailer control module port (22) while the parking brake port (21) is exhausted. The apparatus includes a control unit (100) configured: to control the valve arrangement (10, 20) to exhaust the trailer control module port (22) by connecting the trailer control module port (22) with an exhausted parking brake port (21); and to detect a temporary pressure increase sensed by the sensor (60) and, based on a result, to determine the status of controlling as successful or not.