Image Quality Control Test Pattern Abnormality - Toshiba e-STUDIO281c Service Handbook

[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.
| 320 or above (Y, M and C)
|
220 or above (K)
|
|
|
|
|
|
|
|
(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).
| Normal
|
|
|
|
|
(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 adjust-
ment" ( 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: 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.
e-STUDIO281c/351c/451c
TROUBLESHOOTING
| 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.
|
To (9)
| Abnormal
Correct the items related to the image.
|
To (9)
© 2005 - 2008 TOSHIBA TEC CORPORATION All rights reserved
5 - 88