[CQ] Print quality issues in 4501i

[mdfurqan2012]

We have multiple kyocera task alfa 4501i in field.
currently we are facing print quality problem. When we start printing a job of 25 pages, 1st page print quality ok, 2nd page quality is slightly darker, 3rd is more darker, and on every page it becomes darker even shades becomes on print and print quality becomes worse. When print job of 25 pages completed. I again start printing another job, again 1st page print ok and after that it becomes darker and darker.
I serviced machine, checked drum unit, developer unit, high voltage board, by sawping it with ok machine.
I also upgrade firmware.
kindly guide me.

[Ropariva]

Please tell me you aren’t using generic toner?
These machines were bad enough with the good stuff but when using generics they are truly horrible.
Developer life was supposed to be 600k, but we found it normal to have to replace them at around 300k and that’s with genuine Kyocera toner.

[blackcat4866]

Can we have some image samples please? And what count are the current consumables, drum, developer at?
Try these originals:

[Scottb]

if you can still find 302LH94342 parts seal set all, this will go a long way in helping these machines run less dirty. other than that the following is a good 300K/600K maintenance.
1) remove rear covers and blow out the dust.
2) remove the cover to 302LF94410 and stick the vacuum hose in for about 5 seconds.
3)remove 302N794020 and vacuum out the duct.
4)open the front cover, remove the inner section, remove the developer, remove 302LF94160 vacuum this piece.
5)remove the conveying section, remove the transfer belt assy and vacuum the conveying unit, lower right cover, and 302N994020 registration assembly and vacuum this piece and inside the machine.
Reassemble