- Hewlett-Packard Printers Service Manual

Troubleshooting the Printing System 7-67
Table 7-21. Horizontal Black Lines
Possible Cause Action
Defective Laser
Scanner Assembly or
Engine Controller
Board.
1. See the “Repetitive Defect Ruler” on page 7-73.
2. Reseat connectors on the Laser Scanner and
Engine Controller Board.
3. Replace the Laser Scanner Assembly followed by
the Engine Controller Board, if necessary.
Table 7-22. Horizontal Smudges
Possible Cause Action
Paper path
contamination or
damage.
1. See the “Repetitive Defect Ruler” on page 7-73.
2. Check the Toner Cartridge and replace it if
necessary.
3. Check the Fuser and replace it if necessary.
Table 7-23. Horizontal White Lines
Possible Cause Action
1. Check the Toner Cartridge and replace it if
necessary.
2. Check the Fuser and replace it if necessary.
3. Replace the Laser Scanner Assembly, followed by
the Engine Controller Board, if necessary.