Test pattern check Possible cause/Countermeasure
White image, Abnormal image, Low
density
• Defective laser optics housing unit shutter
• Defective image processing unit
• Low density of test pattern
• Defective BICU
1. Replace the shutter motor.
2. Replace the high voltage power supply unit.
3. Do the forced process control (SP3-011-001) or supply
some toner (SP3-015-xxx).
4. Replace the BICU.
Normal image, but with color
registration errors
• Defective ID sensor shutter
• Defective ID sensor
• Defective BICU
1. Replace the ID sensor shutter solenoid.
2. Replace the ID sensor.
3. Replace the BICU.
After Executing SP2-111-003
• Result: "1" in SP2-194-007
• One of results: "5" (Out of adjustable range) in SP2-194-010, -011, -012.
Test pattern check Possible cause/Countermeasure
The main scan registrations of M, C, Y
are shifted by more than ±15 mm from
the main scan registration of K.
• Defective laser optics housing unit
• Defective BICU
1. Replace the laser optics housing unit.
2. Replace the BICU.
The sub scan registrations of M, C, Y
are shifted by more than ±20 mm from
the sub scan registration of K.
• Defective image transfer belt
• Defective drive units
• Defective BICU
1. Replace the image transfer belt.
2. Replace the drum motor.
3. Replace the BICU.
5. Appendix: Troubleshooting Guide
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