Ricoh Aficio Color 4006, Service Manual

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24 February 1999 SC CODES
13
SC
No.
Item Detection Conditions Possible Causes
Related
SCs
Troubleshooting Procedure Type
SC400 Image transfer
belt bias error
- Timing -
When the image transfer belt
bias is on during printing or a
process control self check
- Condition -
The feedback voltage is 4.8V
or higher, or the PWM value is
50% or higher (indicating a
leak) for 500 ms continuously.
•
Poor connection of
connectors
•
Defective high
voltage supply
board (T1,PCC)
•
Defective I/O
control board
•
Defective main
control board
1. Check if the connectors of high voltage cables and
trigger lines are properly connected on the high voltage
supply board, I/O control board, and main control
board.
2. Clean the bias terminals.
3. Replace the high voltage supply board (T1,PCC).
4. Replace the I/O control board.
5. Replace the main control board.
- Signals to Check -
•
Feedback signal: CN277-B3, TP221, or CN214-A4 on
I/O control board / CN302-A6 or TP158 on main control
board.
•
PWM: CN227-B4 or TP209 on I/O control board.
D
SC422 PCC leak - Timing & Condition -
When the current leak is
detected for 2 seconds, leak
detection starts 1 second after
the PCC turns on. The leak
signal is monitored twice at 1
second intervals. When the
leak condition is detected
twice continuously, this SC is
displayed.
•
PCC unit not
properly set
•
Corona wire
broken
•
Defective high
voltage supply
board (T1,PCC)
•
Defective I/O
control board
•
Defective main
control board
1. Check if the PCC unit is properly instaled.
2. Replace the corona wire if it is broken.
3. Check if the connectors on the terminal and high
voltage supply board (T1,PCC) are properly connected
and if the cables are damaged.
4. Clean the receptacle.
5. Replace the high voltage supply board (T1,PCC).
6. Replace the I/O control board.
7. Replace the main control board.
- Signals to Check -
•
Leak detection: CN227-B1 or TP294 on I/O control
board.
D