MX-C250 TROUBLESHOOTING 7 – 8
F2-23
Discharge lamp trouble (CMY)
F2-39
Process thermister trouble
F2-40
Toner density sensor trouble (BLACK)
F2-41
Toner density sensor trouble (CYAN)
F2-42
Toner density sensor trouble
(MAGENTA)
F2-43
Toner density sensor trouble
(YELLOW)
F2-45
K image density sensor trouble
F2-47
Ozon duct thermister trouble
F2-49
LSU thermister trouble
Cause
Contact trouble between the discharge lamp PWB
(C) and the PCU PWB.
Discharge lamp PWB (C) trouble.
MFPC PWB trouble.
Check & Remedy
Replace the discharge lamp PWB (C).
Check the harness and the connector.
Replace the MFPC PWB.
Cause
Process thermister trouble.
Process thermister harness connection trouble.
MFPC PWB trouble
Check & Remedy
Replace the process thermister.
Check connection of the harness and the
connector.
Replace the MFPC PWB.
Cause
Toner density sensor output abnormality (Sample
level 25 or less, or 231 or above)
Connection trouble of the connector and the
harness.
Developing unit trouble. MFPC PWB trouble
Check & Remedy
Replace the toner density sensor.
Harness and connector connection trouble.
Replace the developing unit.
Replace the MFPC PWB.
Cause
Toner density sensor output abnormality (Sample
level 25 or less, or 231 or above)
Connection trouble of the connector and the
harness.
Developing unit trouble.
MFPC PWB trouble
Check & Remedy
Replace the toner density sensor.
Harness and connector connection trouble.
Replace the developing unit.
Replace the MFPC PWB.
Cause
Toner density sensor output abnormality (Sample
level 25 or less, or 231 or above)
Connection trouble of the connector and the
harness.
Developing unit trouble.
MFPC PWB trouble
Check & Remedy
Replace the toner density sensor.
Harness and connector connection trouble.
Replace the developing unit.
Replace the MFPC PWB.
Cause
Toner density sensor output abnormality (Sample
level 25 or less, or 231 or above).
Connection trouble of the connector and the
harness.
Developing unit trouble.
MFPC PWB trouble.
Check & Remedy
Replace the toner density sensor.
Harness and connector connection trouble.
Replace the developing unit.
Replace the MFPC PWB.
Cause
K image density sensor sensitivity adjustment
trouble.
K image density sensor trouble.
Harness and connector connection trouble.
K image density sensor dirt.
Calibration plate dirt.
Calibration plate solenoid trouble.
MFPC PWB trouble.
Check & Remedy
Replace the K image density sensor.
Check connection of the connectors and the
harness.
Clean the K image density sensor.
Replace the calibration plate.
Replace the calibration plate solenoid.
Replace the PCU PWB.
Use SIM44-2 to adjust the process control sensor
sensitivity.
Cause
The ozone duct thermister trouble.
Harness and connector connection trouble
between the ozone duct thermistor and the
MFPC PWB.
MFPC PWB trouble.
Check & Remedy
Check connection of the connectors and the
harness between the ozone duct thermistor
and the MFPC PWB.
Replace the MFPC PWB.
Cause
The LSU detection temperature is outside of -28
C
- 78
C.
LSU thermister trouble.
Harness and connector connection trouble.
MFP PWB trouble
LSU control PWB trouble.
Check & Remedy
Check connection of the connectors and the
harness.
Replace the MFPC PWB.
Replace the LSU.
