Brother GT-541 Instruction Manual page 100

7. Troubleshooting
(15) Take off your gloves and remove the used Print Head by lifting up the knob.
(16) Remove the Protective Tube from the new Print Head, and then install the new Print Head by
holding the knob, and holding the flat cable with the other hand.
Make sure the V-shaped groove of the Print Head hits the pin.
Protective Tube
Pin
90
Knob
GT-541
V-shaped
groove