Ricoh A229 Service Manual page 434

Rev. 12/15/98
SC370-07: Potential sensor error 7
Definition- [D]
When adjusting the drum potential (VH) for half tone at the process control initial
setting, the drum potential sensor detects that VH does not become –300 + 20 V
even though the LD power has been changed twenty times five times.
- Possible causes -
• Potential sensor defective
• Poor connection between the potential sensor and the I/O board (IOB)
• IOB defective
• Poor connection between the drum unit and the I/O board (IOB)
• LD unit defective
• Poor drum cleaning
SC390-1: TD sensor error 1
-Definition- [B]
The TD sensor output voltage is less than 0.5V or more than 4.0V 10 times
consecutively during copying.
- Possible causes -
• TD sensor defective
• Poor connection between the TD sensor and the I/O board (IOB)
• I/O board (IOB) defective
SC390-2: TD sensor error 2
-Definition- [B]
One of the following TD sensor output voltages is detected during TD sensor
initial setting.
1) Less than 2.5V when the maximum PWM (255) is applied to the TD sensor.
2) 2.5V or more when minimum PWM (0) is applied to the TD sensor.
- Possible causes -
• TD sensor defective
• Poor connection between the TD sensor and the I/O board (IOB)
• I/O board (IOB) defective
SM
SERVICE CALL CONDITIONS
6-11 A229