Tektronix Phaser 780 Color, Service Quick Reference Manual

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Phaser 780 Color Printer
5. Inspect the image on the drum. Is there a normal test print image, without
any band deletions, visible on the drum? If yes, go to Step 6. If not,
replace the imaging unit.
6.
Inspect the image on the surface of the accumulator belt? Is there a
normal test print image, without any horizontal band deletions, visible on
the surface of the accumulator belt? If no, replace the accumulator belt.
7. Inspect the image on the sheet of paper just before the paper enter the
fuser. Is there a normal test print image, without any band deletions,
visible on the sheet of paper? If not, replace the second bias transfer roller.
8.
Generate a test print and open the front cover just as the sheet of paper
exits the fuser.
9. Inspect the image on the sheet of paper just after the paper exits the fuser.
Is there a normal test print image on the sheet of paper before entering the
fuser but the image has visible horizontal band deletions after it exits the
fuser? If yes, replace the fuser roll cartridge.
10. Make another test print. If the problem still occurs, replace the fuser.
11.
Remove the top cover.
12.
Turn the carousel frame and inspect the magnet roller of each of the four
developer assemblies. Do the magnet rollers of each developer assembly
appear smooth, evenly formed, without any low spots, and without
obvious contamination? If not, replace the defective developer assembly.
13.
Replace the high voltage power supply.
14.
Replace each of the four developer assemblies, one at a time.