Ricoh SP 8400DN Field Service Manual page 1349

Cause:
Possible causes of SC672 include:
•
USB communication path failure (USB cable, IPU)
•
CTL boot up error and/or operation panel boot up error due to abnormal break in operations of CTL.
Possible causes of operation panel cannot light include:
•
USB communication path failure (USB cable, IPU)
Operation panel cannot communicate with CTL due to CTL boot-up error
[A]: Operation Panel
[B]: IPU
[C]: Controller board
[D]: USB cable
Solution:
Do the following.
1. Turn the machine power OFF/ON.
2.
Do the action in the flowchart below to determine the cause and best course of action when SC672 occurs.
Flowchart to determine parts to replace when SC672 occurs
6.Troubleshooting
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