The present invention relates to an apparatus for connecting appliances/tools to a tool arm, wherein the apparatus includes: an upper fastening portion (10B) adapted to be supported by a tool arm (2) of a machine; a lower fastening portion (16A) arranged to support at least one appliance/tool (5) to be maneuvered by the machine, wherein the lower fastening portion (16A) has one or more recesses (40,41) arranged to receive corresponding fastening pins (30,31) of the appliance/tool (5) for engagement when connecting the appliance/tool to the apparatus; and at least one locking element (50) arranged to be in a locking position for locking the appliance/tool to the apparatus when the fastening pins are in engagement with the recesses (40,41); wherein the apparatus further includes: at least one first sensor (70) arranged to verify that the locking element (50) occupies a correct locking position; and at least one second sensor (80) arranged to verify correct engagement between the fastening pins (30,31) and the recesses (40,41). The invention also relates to a method.