Toshiba e-STUDIO5540C Service Manual page 166

Step Check item
2 Check "Output value display
of image quality sensor /
High-density pattern (05-
2731-0 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 628 or above, it
is defined as high-density
pattern abnormality.
3 Set the values of "Image
quality closed-loop control /
Contrast voltage (08-2486)"
and "Drum surface potential
sensor control setting (08-
2561)" to "0" (Invalid).
4 Output the image quality
control test pattern (04-270)
more than one time and the
list print ([9][START]) in the
adjustment mode (05), and
check the patch of the color
identified in step (1) to see if
the image is abnormal.
5 Replace the image quality
sensor or LGC board.
6 Set the values of "Image
quality closed-loop control /
Contrast voltage (08-2486)"
and "Image quality closed-
loop control / Laser power
(08-2561)" to "1" (Valid).
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Result
Under
628 (Y,
M, C
and K)
628 or High-density pattern abnormality
above Check if the laser shutter is working properly.
(Y, M, C <Procedure>
and K) 1. Take off the process unit so that the laser
shutter can be easily seen.
Clean around the laser shutter if the
developer has been spilled over.
2. While pressing the digital keys [0] and [3]
simultaneously, turn the power ON.
3. Key in "201".
4. Press the [START] button and check if the
shutter is opened and then closed
(reciprocating 1cycle).
Check if the developer unit has been installed
properly.
1. Visually check the installation status of the
developer unit, and correct it if there is any
abnormality.
To (8) (If you have already performed this
checking cycle once, proceed to step (3).)
Normal
Abnorm Abnormal image:
al Blank print, Solid print, White banding, Color
banding, White spots, Poor transfer, Uneven
image density, Faded image (low density),
Uneven light distribution, Blotched image.
Blank print: including when one of the YMCK
colors is not printed.
Correct the abnormal image.
Proceed to step (6).
8 - 165
Measures
e-STUDIO5540C/6540C/6550C/5560C/6560C/6570C
ERROR CODE and TROUBLESHOOTING
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