
17 January, 2003
SC TABLE
4-29
SC No.
Item
Definition
Possible Cause
Related
SCs
Troubleshooting Procedure
Type
SC 680 BCU/ MUSIC
communication
error
After the engine CPU sends a
message, the Music CPU does
not respond within five
seconds three consecutive
times.
•
Toner cartridge
memory chip loose
connection
•
Memory chip problem
•
Memory chip cable
wiring problem
1. Turn the main switch off and on.
2. Check if the toner cartridge is
installed correctly.
3. Replace the toner cartridge.
4. Check if the harnesses are not
damaged.
5. Replace the BCU.
SC 685
(CF)
SBU-IPU
communication
error
•
During data transfer, a
checksum error occurs.
•
During any operation except
initialization, the SBU sends
a hardware-reset
acknowledgement to the
IPU.
•
Scanner unit cable
connector loose
•
SBU board defective
•
IPU board defective
•
External noise
1. Turn the main switch off and on.
2. Shut out the external noise.
3. Check the cable connection of the
scanner unit.
4. Replace the SBU board.
5. Replace the IPU board.
B
SC 686
(CF)
BCU-IPU
communication
error
•
After the machine is
powered on or recovering
from the power save mode,
timeout occurs during BCU
communication.
•
The break signal is received
after the communication is
normally established with
the BCU.
•
Timeout occurs while the
communication with the
BCU is retried after a
communication error.
•
Board connector
between BCU and
controller loose
•
Board connector
between controller
and bridge board
loose
•
Board connector
between bridge board
and IPU loose
•
BCU board defective
•
IPU board defective
•
Controller board
defective
•
Bridge board
defective
1. Turn the main switch off and on.
2. Check the cable connection between
the board connector and BCU.
3. Check the cable connection between
controller and bridge board.
4. Check the cable connection between
bridge board and IPU.
5. Replace the BCU board.
6. Replace the IPU board.
7. Replace the controller board.
8. Replace the bridge board.
B
SC 687 Memory
address
command error
The BCU does not receive a
memory address command
from the controller 60 seconds
after paper is in the position for
registration.
•
Loose connection
•
Defective controller
•
Defective BCU
1. Turn the main switch off and on.
2. Check if the controller is firmly
connected to the BCU.
3. Replace the controller.
4. Replace the BCU.