Brother GTX600NB Instruction Manual page 215

(5) Unlock the upper left-hand-side cover and top cover and clean the suction cap.
Unlock and open the right-hand-side cover and clean the nozzle guard.
Two types of clean sticks are provided. Use either the clean stick T or R depending on what you want to clean.
<TIPS>

For the cleaning method, refer to the description mentioned below.
Locations to be
cleaned with clean
stick T
Locations to be
cleaned with clean
stick R
(6) After the cleaning is completed, close all the covers.
<NOTE>

Dispose of any waste resulting from the cleaning in accordance with applicable laws and ordinances.
<TIPS>

Then, the head cleaning will be performed to prevent any ink from drying up.

Because the cleaning cup will be reused, rinse it in clean cleaning solution and store it in a safe place.
Precautions to keep good printing quality/use printer over the long term
On the white side
6-47
On the color side
Suction cap
The nozzle guard
surface and between the
nozzle guard and nozzle
X1013