Background Fogging - Toshiba e-STUDIO281c Service Handbook

4) Background fogging

Cause/Section Step
Density repro- 1 Check the gradation reproduction.
duction
Printer section 2 Check the printer output image.
Scanner 3 Check if the original glass, mirrors
or lens is dirty.
Parameter 4 Check the image processing
adjustment value parameters.
5 Adjust the image processing
parameters.
Cover 6 Is the cover installed properly?
(Is the drum exposed to the exter-
nal light?)
Auto-toner 7 Is the auto-toner sensor normal?
8 Is the toner supply operating con-
stantly?
© 2005 - 2008 TOSHIBA TEC CORPORATION All rights reserved
Fig. 5-4
Check items
Perform the forced performing of
image quality closed-loop control
(05-395) and then automatic
gamma adjustment.
Output the test patterns and check
them.
Color: using 04-231 for each color
Black: using 04-113
Clean it.
Check the value of offsetting
adjustment for background pro-
cessing (color), background adjust-
ment (black) and background peak
adjustment for range correction
(black).
While checking the above encircled
image, adjust the reproduction level
by the offsetting adjustment for
background processing (color),
background adjustment (black) and
background peak adjustment for
range correction (black).
Correct it.
Check the operation of autotoner
sensor and readjust.
Check the motor and circuits.
5 - 117
Measures Remarks
See step 6
if defects
occur.
e-STUDIO281c/351c/451c
TROUBLESHOOTING
5