I am having the same issue with only 75 prints on the machine. The cartridge monitor showed almost full prior to the first error, except mine said check black cartridge, and when I restarted I got messages saying check yellow cartridge AND check magenta cartridge. I also cleaned all areas as shown in user manual,
My new Xerox 6022 came with toner cartridges installed. They ran out quickly so i purchased a full set to replace them. I purchased Xerox Toner for the Phaser 6020/6022. The Cyan Cartridge number is 106R02756. When I turn the printer on, I get the 3 messages:
Low Density 093-921 Printer
Check Cyan Cartridge
I uninstalled and re-installed the cartridge numerous times and re-started without success. On one occasion after restart, the message changed to "CHECK YELLOW CATRIDGE", then back to CYAN for a few more times.
Thw printer worked fine with the original toners until the yellow ran out.