Trouble Shooting
| Step | Cause | Solution | Parts |
| 1 | TR(Transfer roller) of the drum unit does not rotate smoothly. | Clean TR (see blow). | |
| 2 | Drum unit defective. | Replace the drum unit. | Drum (015-0289-21) |
| 3 | Develop unit defective. | Replace the develop unit. | Develop unit (015-0204-21) |
| 4 | HVPS (High-Voltage Power Supply) defective. | Replace HVPS. | HVPS (005-3141-9-SP) |
| 5 | Main board defective. | Replace the main board MBA890. | Main board: AM7630i (004-3479A-9-SP) AM7640i (004-3479B-9-SP) AM5630i (004-3479C-9-SP) AM5640i (004-3479D-9-SP) |
Clean TR (transfer roller)
Loosen 3 fixing screws to remove the metal frame. Check the Transfer roller position and confirm whether there are any foreign object.
