If you wired the transducer temp wires (white and Brown) to the inside of the sounder, your setting for the UHD sounder should be selected as "LF". If you wired the wire to the external temp connector (Aka MJ) then the setting would be MJ. Sounders like the DFF3 offer both a low and high side connection for temp, hence the third option (HF). Yours should show temp if you select LF under the sounder setup and then ensure that the DFF1-UHD is selected as your temp source under your "Data Sources" setting of your initial setup.