PIXMA G6020 code 5200 issue wont resolve

[BeyondDesign]

i have had my g6020 for a few years and had no issues until recently. i performed regular maint. and kept the ink wells full where it printed  great over and over again. 

Then after not being used for a period of time i started experiencing a fade only on the color side . i read the manual and forum which led me to all the nessesary cleaning and flush procedures i performed in the past . but no fix , what else can i do to restore print functions ? is there somthing im overlooking? ty in advance

[shadowsports]

Greetings,

Here are suggestions for resolving error 5200 on the G6000 series.

https://ij.manual.canon/ij/webmanual/ErrorCode/G6000%20series/EN/ERR/5200.html?ref=5200

Note.  Printheads do have a service life.  They are subjected to high current and heat over the course of their life.  Depending on use, print quality can degrade over time.  Print quality issues can be related to age, clogs, air in the lines, etc.  Have you performed a nozzle test pattern?  I suggest you perform the steps in the manual and see if that helps.