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Confidential
■ Error code 9903
An error occurred during patch data printing in manual color registration performed from the
control panel.
<User Check>
• Check if the toner cartridges are set in the correct order of colors.
• Replace the toner cartridge.
• Replace the drum unit.
• If the belt unit has a scratch, replace it.
• If “WT Box End Soon” is displayed on the LCD and the belt unit has dirt, replace the waste
toner box.
Step Cause Remedy
1
Dirt on the registration mark
sensor L / registration mark
sensor R
Clean the registration mark sensor L /
registration mark sensor R.
2
Connection failure of the
registration mark sensor L /
registration mark sensor R
harness
Reconnect the registration mark sensor L /
registration mark sensor R harness.
3
Failure in printed measurement If failure occurs when printing “K/W/Y/M/
C” in “Function code 71”, refer to “4.3
Troubleshooting for Image Defects” in this
chapter and take a measure.
4
Registration mark sensor L or
registration mark sensor R failure
Replace the registration mark sensor
ASSY.
5 Main PCB failure Replace the main PCB.