Service manual
30 July, 2001 SC TABLE
4-25
SC No. Item Definition Possible Cause
Related
SCs
Troubleshooting Procedure Type
SC 680
BCU/ MUSIC
communicatio
n 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 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.
SC 722 Finisher jogger
motor error
• The jogger fences of the
finisher donot return to
home position within a
specific time.
• The finisher jogger motor
does not leave home
position within a given time.
• Defective jogger H.P.
sensor
• Loose connection
• Defective jogger
motor
1. Turn the main switch off and on.
2. Check the connection of jogger H.P.
sensor and jogger motor connectors
3. Replace the jogger H.P. sensor.
4. Replace the jogger motor.
SC 724
Finisher staple
hammer motor
error
Stapling does not finish within
150 ms after the staple
hammer motor turns on.
• Staple jam
• Loose connection
• Overload caused by
stapling too many
pages
• Defective staple
hammer motor
1. Turn the main switch off and on.
2. Check if the staple hammer motor
connector is properly connected.
3. Check if the staple jam occurs.
4. Replace the staple hammer motor.
SC 725 Finisher stack
feed-out motor
error
The stack feed-out belt H.P.
sensor does not activate within
a specified time after the stack
feed-out motor turns on.
• Defective stack feed-
out H.P. sensor
• Loose connection
• Stack feed-out motor
overload
• Defective stack feed-
out motor
1. Turn the main switch off and on.
2. Check if the connectors of the stack
feed-out H.P. sensor and motor are
properly connected.
3. Replace the stack feed-out H.P.
sensor.
4. Replace the stack feed-out motor.