Cp5225 unlock service menu - HEWLETT-PACKARD Color LaserJet CP5225 Printer

If a service person can do it you should be able to I think. See link below for assistance/support for your device
HP Color LaserJet Professional CP5225 Printer series

You need to put them in Tray 1 / multipurpose tray

FIRMWARE - corrupted, you have to down load firmware.

PRESS HOME BUTTON & OPEN FOLLOWING MENUS.
ADMINISTRATION ~ MANAGE SUPPLIES ~ RESET SUPPLIES ~ NEW FUSER KIT,
THEN USE DOWEN ARROW BUTTON TO HIGHLIGHT " YES " ITEM THEN PRESS OK.

clean mirrors on the laser unit all four mirrord

You can change it in the Display Settings Menu. Print a menu map under administration/information to navigate your way

In the settings menu there should be a economy mode which will lighten up the print.

HP has a list of solutions for print quality problems. Have you tried all the solutions suggested here?

Troubleshoot problem for HP Color LaserJet Professional CP5225 Printer...

There were also a couple Mac specific solutions available (links look the same but are different). Both solutions are about prints being different than expected.

Troubleshoot problem for HP Color LaserJet Professional CP5225 Printer...

Troubleshoot problem for HP Color LaserJet Professional CP5225 Printer...

I am an HP employee.

need to replace those colour cartridges

replace the cartridge or give it a good clean