e-STUDIO3511/4511 TROUBLESHOOTING 5 - 72 November 2003 © TOSHIBA TEC
[CE40] Image quality control test pattern abnormality
(1) Use "Image quality control abnormal detection counter Y to K display/0 clearing (08-573 to 576)"
to check the abnormal occurring condition for each color.
(2) Check “Output value display of image quality sensor / Low-density pattern (05-391-0 to 3)” to
check if the low-density pattern abnormality occurs for each color. The values under 320 for Y, M
and C, and under 220 for K are defined as low-density pattern abnormality.
Under 320 (Y, M and C)
Under 220 (K)
Low-density pattern abnormality
Check the transfer belt. If the cleaning is poor, correct the transfer belt
around its cleaning blade.
320 or above (Y, M and C)
220 or above (K) To (9)
(3) Check “Output value display of image quality sensor / High-density pattern (05-390-0 to 3)” to
check if the high-density pattern abnormality occurs for each color and identify the color which
pattern is abnormal. If the value is 630 or above, it is defined as high-density pattern abnormality.
(4) Set the values of “Image quality closed-loop control / Contrast voltage (08-556)” and “Image
quality closed-loop control / Laser power (08-557)” to “0” (Invalid).
(5) Perform “Enforced performing of image quality open-loop control (05-394)”.
(6) Output the image quality control test pattern (04-270) more than one time and check the patch of
the color identified in step (3) to see if the image is abnormal (Note).
Abnormal
Correct the items related to the image.
Normal To (9)
(7) Replace the image quality sensor.
(8) Set the values of “Image quality closed-loop control / Contrast voltage (08-556)” and “Image
quality closed-loop control / Laser power (08-557)” to “1” (Valid).
(9) Perform “Enforced performing of image quality open-loop control (05-394)” and make sure it is
completed normally. (Error [CE40] does not appear.) Then perform “Automatic gamma adjustment
“ ( Chapter 3.5.1 and 3.6.1).
(10) Clear all "Image quality control abnormal detection counter Y to K display/0 clearing (08-573 to
576)".
Note
Abnormal image:Blank print, Solid print, White banding, Color banding, White spots, Poor transfer,
Uneven image density, Faded image (low density), Uneven light distribution, Blotched
image
04/05