I have a Horizon T900 treadmill. There is a little backdoor to display information or tweak the the treadmill settings. I haven’t played much with them for fear of goofing up my treadmill.

You can get into the engineering mode by holding the “incline +” and the “speed -” buttons at the same time for about 5 seconds. Then you can use the speed +/- buttons to go between the different modes. Then you can hit the Enter button to select a particular engineering mode. You can press and hold the Stop button to exit.

Engineering Mode 0 (ENG0)
Display Test

Engineering Mode 1 (ENG1)
Hardware Test

Engineering Mode 2 (ENG2)
Auto Calibrate
• Press, “ENTER” to select. Press, “START” to begin. The treadmill running belt will begin to move automatically and the auto-calibration sequence will properly set and store the speed values.
• Upon successful calibration, the treadmill will beep several times. The console will automatically exit Engineering Mode and return to the start-up screen

Engineering Mode 3 (ENG3)
Switch Function

Engineering Mode 4 (ENG4)
Information
• Press, “ENTER” to select. Accumulated time and distance will display on console.
• Press and hold the Stop button to back out of each menu. (or just turn the treadmill off).

I don’t know what the other engineering modes do. If someone else knows, I’d love to hear about them. I suppose you could just select each mode, and see what happens. But as I said, I am afraid of goofing something up on my treadmill and I need it to do my marathon training.