Go to Service Mode > State Confirmation > I/O Check Mode
In the screen shot below you will see the I/O Code with value 1-12. Change it by typing on the keypad, click High/Low to switch from 1st value to 2nd value and vice versa. Click Start to do an output check on the part.
Here are the most common I/O Codes that we use:
Toner Supply Assy *Make sure to pull out all the toner bottle before proceeding with the I/O check 1-12 | Toner bottle motor (M15)
Paper Feed Drive Assy 28 - 00 | Paper feed motor/Up (M11) 28 - 03 | Paper feed motor/Lw (M12)