HP Color LaserJet CM4730 Multifunction Printer series - Manual (Page 287)

Color fade in all colors
Defect description
All colors are faded in one or more locations on the page.
Possible causes
The device needs to be calibrated. Operating environment or media in use does not meet HP
specifications.
Troubleshooting and suggestions
1. Calibrate the MFP.
2. Make sure that the environmental specifications for the device are being met.
ENWW Correct print quality and copy quality problems 271