A terminal sharing arrangement allows output terminals of an apparatus such as a television signal receiver or other device to be used for both outputting signals such as audio signals, and providing a diagnostic function. According to an exemplary embodiment, the apparatus includes a first terminal operative to output a first output signal during a first mode, and to receive a first diagnostic signal during a second mode. A second terminal is operative to output a second output signal during the first mode, and to output a second diagnostic signal during the second mode.