Samsung SF4500, Service Manual

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Samsung Electronics 8-1
8. Troubleshooting
8-1 SCANNER
PROBLEM ITEMS TO BE CHECKED HOW TO SOLVE
White Copy
Black Copy
Defective image
quality
• Check shading profile.
• Check white Ref. value and black
Ref. value.
• Check CIS signal input level.
• Check shading profile.
• Check if CIS LED is on/off.
• Check white ref.value and black
Ref.value.
• Check CIS signal input level.
• Check shading profile.
• Check printing quality.
• Remake shading profile in the tech mode.
• Replace U17 if it is defective.
(white Ref. =3.0V. black Ref=1.4V)
• Check if it is 3.0V when operating and
1.5V when idle. If defective, replace CIS.
• Remake shading profile in the tech mode.
• Check if CIS harness is pluged.
• If defective, replace U17.
(white Ref.=3.0V. black Ref=1.4V)
• Check if it is 3.0V when operating and
1.5V when idle. If defective, replace CIS.
• Remake shading profile.
• Refer to printing quality.
8-1-1. COPY
PROBLEM ITEMS TO BE CHECKED HOW TO SOLVE
Scanning error
Defective image
quality
• Check if printer cable is installed.
• Check if printer cable is appropriate.
• Check how TWAIN driver is installed.
• Check parallel port I/P part.
➀
Check the early state of J2 print
signals.: #1, 10-14, 31, 32, 36
➁
Check U4 input/output signals.
➂
Check input/output signals of
U16-43 ~ 51, U16 - 53 ~ 61.
Refer to ‘1.COPY’.
• Check if printer cable is correctly installed.
• Check if printer cable is proper for
IEEE1284.
• Reboot the system after TWAIN driver is
installed again.
• Replace the main PBA.
Refer to ‘1.COPY’.
8-1-2. PC-SCAN