A: P-0 is often "test mode" or "manual override." Exit by power cycling.
If you still cannot find it, this guide covers 95% of the original manual content, supplemented with community-sourced tips. xy-w58cdt9-av7 manual
The is a driver board used for driving LCD screens, typically converting HDMI, VGA, or AV signals to LVDS. Basic Operation (OSD Board) A: P-0 is often "test mode" or "manual override