How To Use The Test Print - Canon imageRUNNER ADVANCE C255 Series Service Manual

4. When the TYPE is set to "5" in step 2, specify the density in the following service mode.
COPIER > TEST > PG > DENS--Y: Y
COPIER > TEST > PG > DENS--M: M
COPIER > TEST > PG > DENS--C: C
COPIER > TEST > PG > DENS--K: Bk
5. Press start key.

How to use the test print

■ 16 Gradations (TYPE = 4)
This test print is mainly used to check gradation performance, fogging, white lines, and uneven density between the front and
rear sides.
Check item Checking Method
Gradation Check that the 16 density gradations
are recognizable.
Fogging Check whether fogging appears only in
the blank area.
White line Check the entire image for any white
line.
Uneven density Check for any uneven density between
(rear/front) the rear and front sides.
■ Full Page Halftone (TYPE = 5)
This test print is mainly used to check for black lines, white lines, and uneven density.
Drum Unit error or Laser Scanner Unit error
Drum Unit error or Laser Scanner Unit error
Drum Unit error or Laser Scanner Unit error
Drum Unit error, Laser Scanner Unit error, or soiling on the laser light path
322
6. Troubleshooting
Assumed cause