Xerox Phaser 7700 Service Manual page 291

9-268 Phaser 7700 Color Laser Printer
Interpreting Solid Fill Test Prints:
Non-uniformity in any one color may indicate
a problem with the developer or print units.
Light streaks in one color indicate developer
or debris blocking the laser.
Dark streaks in one color indicate a problem
with the developer or print units.
Repeating spots in one color indicate a
problem with the print unit. Non-repeating
spots in all colors indicate problems with the
transfer belt.
Things to look for:
Uniformity in each color
Streaks
Spots
Repeating spots
Any one weak color may indicate a
faulty developer, print unit, or first
transfer.
Weak colors may also be caused by a
defective high-voltage power supply.
If all colors are weak, this could
indicate a problem with the ADC or
second transfer systems.
S7700-289
"Worm tracks" or wrinkles may be
caused by the fuser.