Samsung ProXpress M453x series Service Manual page 207

8) Background
Description : Light dark background appears in whole area of the printing.
Probable Cause
Does recycle paper be used?
The life of the imaging unit has been expired
The output from the HVPS is abnormal.
Copyright© 1995-2017 SAMSUNG. All rights reserved.
Solution
Use the proper sheet for the job at hand.
Replace the imaging unit.
Replace the HVPS board.
4. Troubleshooting
4-112