Quoting from manual above (may be similar model if not the same.)
7. Turn on or turn off the display demo mode.
The console features a display demo mode,
designed to be used if the treadmill is displayed
in a store. While the demo mode is turned on, the
console will function normally when you plug in
the power cord, press the power switch into the
reset position, and insert the key into the console.
However, when you remove the key, the screen will
show a demo presentation.
To turn on or turn off the display demo mode, first
touch the Demo Mode button. Next, touch the On
checkbox or the Off checkbox.