Dirty Background - Ricoh FT5535 Service Manual

1.3 DIRTY BACKGROUND

- Problem -
1. Dirty background at image density level 4 (manual setting).
2. Copies made in ADS mode have a dirty background.
- Possible Causes -
1. V correction failure
L
• Very dirty optics (V
Deteriorated exposure lamp (maximum output cannot give sufficient
•
light intensity)
• Failure of the dc power supply board
Dirty erase lamp unit
•
2. V correction failure
R
CB (development bias) high voltage supply board failure
•
• Poor development bias terminal contact
The development bias is grounded
•
3. The OPC drum is not grounded properly
4. ADS mode
Improper ADS Density setting (SP5-106)
•
ADS Sensor board failure
•
• CB high voltage supply board failure
Incorrect adjustment of the ADS sensor (SP4-201)
•
Sensitivity of the ADS sensor is not correct for the original
•
5. High toner density
Improper setting of the drum charge voltage adjustment (SP2-001)
•
Improper V pattern bias (SP2-203)
•
SP
Dirty erase lamp unit
•
6. Drum charge roller thermister error
• Connector of the drum charge roller thermistor id not connected
properly.
Broken drum charge roller thermistor
•
FSM
CÓPIA NÃO CONTROLADA
correction cannot compensate)
L
6-5
CÓPIA NÃO CONTROLADA
A156/A160/A162