Mazda RX-8 Workshop Manual page 3155

4. Verify the software version.
5. To stop the on-board diagnostic test mode, to the LOCK position.
Connection condition verification
1. Turn the ignition switch to the ACC or ON position.
2. Turn the audio power to OFF.
3. While pressing the POWER/VOLUME switch, simultaneously press the PRESET switch 4 and
the SEEK switch (down) for 3 s or more.