Canon MF720 Series Service Manual page 157

■ After replacing CIS units
1. AGC adjustment
1. Entering a provisional value
Change the foregoing values to "1,000".
• COPIER > ADJUST > CCD > LED-BW-R
(Adjustment of LED light-up time (R) at B&W
reading)
• COPIER > ADJUST > CCD > LED-BW-G
(Adjustment of LED light-up time (G) at B&W
reading)
• COPIER > ADJUST > CCD > LED-BW-B
(Adjustment of LED light-up time (B) at B&W
reading)
Change the foregoing values to "1,200"
• COPIER > ADJUST > CCD > LED-CL-R
(Adjustment of LED light-up time (R) at color
reading)
• COPIER > ADJUST > CCD > LED-CL-G
(Adjustment of LED light-up time (G) at color
reading)
• COPIER > ADJUST > CCD > LED-CL-B
(Adjustment of LED light-up time (B) at color
reading)
2. Adjust the white level in the following service mode.
• COPIER > FUNCTION > CCD > BW-AGC
(CIS intensity adjustment in ADF (B&W))
• COPIER > FUNCTION > CCD > CL-AGC (CIS
intensity adjustment in ADF (color))
3. If the operation was "successful", this procedure is
completed. (There is no need to write the value on
the service label.)
4. How to judge whether the operation was successful
or failed
Whether the operation was successful or failed is
not shown on the UI, so perform the following
procedure to judge if the operation was successful
or failed.
B&W mode
• COPIER > ADJUST > CCD > LED-BW-R
(Adjustment of LED light-up time (R) at B&W
reading)
• COPIER > ADJUST > CCD > LED-BW-G
(Adjustment of LED light-up time (G) at B&W
reading)
• COPIER > ADJUST > CCD > LED-BW-B
(Adjustment of LED light-up time (B) at B&W
reading)
Check the foregoing values. If all of them remain
"1,000", the operation result is judged to be "failed".
If the operation result is judged to be "failed", turn
OFF and then ON the power, and execute COPIER
> FUNCTION > CCD > BW-AGC again.
Color mode
• COPIER > ADJUST > CCD > LED-CL-R
(Adjustment of LED light-up time (R) at color
reading)
• COPIER > ADJUST > CCD > LED-CL-G
(Adjustment of LED light-up time (G) at color
reading)
• COPIER > ADJUST > CCD > LED-CL-B
(Adjustment of LED light-up time (B) at color
reading)
Check the foregoing values. If all of them remain
"1,200", the operation result is judged to be "failed".
If the operation result is judged to be "failed", turn
OFF and then ON the power, and execute COPIER
> FUNCTION > CCD > CL-AGC again.
2. Automatic adjustment of the stream reading
position
1. Entering a provisional value
Set the value of
• COPIER > ADJUST > ADJ-XY > STRD-POS
(Adjustment of reading position at ADF stream
reading)
to "-20".
2. Automatic adjustment of the stream reading
position
Execute
• COPIER > FUNCTION > INSTALL > STRD-
POS (Scan position auto adj in ADF mode)
If the operation was successful, write the value of
STRD-POS on the service label.
149
4. Disassembly/Assembly