Follow the instructions below:

1. Turn off the printer.


2. Press and hold the Feed/Pause Button and then turn on the printer.


3. For the Black Mark Sensor
   Release the button when the LED is lit in green/amber (blinks 5 times alternately) after the green LED flashes five times.
   The LED color will change in the following order:
   Amber > Red (5 times) > Amber (5 times) > Green (5 times) > Green/Amber (blinks 5 times alternately) (Release the button here) > Red/Amber (blinks 5 times alternately) > Green (lit)
   
   For the Gap Sensor
   Release the button when the LED is lit in red/amber (blinks 5 times alternately) after the green/amber LED flashes five times.
   The LED color will change in the following order:
   Amber > Red (5 times) > Amber (5 times) > Green (5 times) > Green/Amber (blinks 5 times alternately) > Red/Amber (blinks 5 times alternately) (Release the button here) > Green (lit)

   You can also calibrate by using the BPM (Brother Printer Management Tool).