Magenta color missing

Hi i'm a printer Technician
The problem of your printer could be that the surface of the printhead is dirty, and the Cleaning pad/tab doesn't work so good..

Here's a guide i wrote that I done multiple times on my customers printers:

1. Power on the printer, and when the carriage moves from the right to the left side instantly disconnect the power cord.

2. Move the Printer carriage (where the cartridges are installed) on the EXTREME LEFT side, please do it very slowly!

3. Take a syringe of hot water but not boiling, MAX. 70-75 °C

4. Expect the extreme right side of the printhead.. You could be able to see a little squared pad, dirty of ink, and on the left side of that PAD you could see a little rubber strip.

5. Take a tissue of paper and dab the furface of the Cleaner Pad (The squared pad you seen)

6. Take a new tissue of paper and place on it some hot water

7. Without burning your hands try to clean as soon as possible the rubber strip on the right part of the Pad.
It would be completely without ink on it

8. Take the hot water syringe and place some hot water on the Cleaner Pad (the amount of water is proportionate to the printer, you have to place water until you see that the surface of the pad is COMPLETELY full of water.

9. Gently move the carriage VERY SLOWLY on the extreme right side of the printer (where there's the Cleaning Pad)

10. Leave the printer like so for 3-5 hours, then restart the printer and do 2-3 cleaning cycles, better with a brand new black cartridge

11. Do a test print (Nozzle Check) and see if there are some changes!

Hope the Best!!
ADCSFXworks Printing Center