Phenomena
Cause
positions
Cause 1
Cause 2
Remedy
Low
density
Developing
unit
Too much distance between developing roller and
OPC unit
Undertoner (insufficient toner supply)
Insufficient development (Insufficient toner on the
developing roller)
Developing shutter ring defect
OPC drum unit installation incomplete
Developing unit positioning collar defect (deformation,
attachment of foreign material)
Developing unit installation incomplete
Doctor gap improper
Developing roller main electrode position improper
Developer defect
Toner concentration sensor defect
Developing shutter spring defect
Developing shutter defect
Developing roller rotation improper
Foreign material intrusion
Developing unit replacement
Drive section
Toner supply insufficient
Developing shutter ring defect
Toner clutch defect (color)
Toner motor defect (black)
Developing shutter clutch solenoid position improper
Developing shutter clutch defect
Developing shutter drive gear defect
Developing roller clutch defect
Toner clutch replacement
Developing shutter clutch solenoid position adjustment
Developing shutter clutch replacement
Developing shutter drive gear replacement
Developing roller clutch replacement
Optical
section
Laser
quantity
insufficient
Scanner unit defect, dirt
Optical
unit
cleaning
Optical unit replacement
OPC
drum
unit
Too much distance between developing roller and
OPC drum
Main charger charging failure (too high)
OPC drum unit mechanism section defect
OPC drum defect
Main charger defect
Main charger cleaning
OPC drum unit replacement
High voltage
PWB
Main charger output failure (too high)
Developing bias voltage failure (too low)
Transfer voltage failure
High voltage PWB defect
High
voltage
PWB
replacement
Discharge lamp
Discharge lamp light quantity insufficient
Discharge lamp does not turn on.
Discharge lamp dirt
Discharge lamp defect
Discharge lamp cleaning
Discharge lamp replacement
Transfer drum
section
Uneven
transfer
Transfer drum defect
Dew
Too much nip between transfer drum and OPC drum
Transfer drum replacement
Transfer drum holding section repair
Charger roller
lift drive section
Charger roller pressure failure (transfer drum)
Lift
clutch
defect
Lift mechanisms section (cam, gear, spring) defect
Paper feed unit installing position improper
Lift clutch adjustment, replacement
Lift mechanism parts replacement (cam, gear, spring)
Paper feed unit installing position correction
Others
Development insufficient (insufficient toner and
developer on the developing roller)
Machine tilt
Machine level adjustment
Sensor
Temperature/humidity sensor malfunction
Toner concentration sensor malfunction
Image density sensor malfunction
Temperature/humidity sensor defect
Toner concentration sensor (developing unit) defect
Image density sensor defect
Temperature/humidity sensor replacement
Developing unit replacement
Image density sensor replacement
Image density sensor cleaning
11 – 33
SHARP SERVICE MANUAL JX8200SM [11] TROUBLESHOOTING