Diagonal Unevenness

Assumed cause
  • Printing unevenness due to paper feed failure

Defect-related parts
  1. Belt Drawer Unit
    Drop in paper suction force due to dirt on Paper Feed Belt surface or charging roller
  2. Anti Static Brush Unit
    Drop in paper suction force due to dirt of Anti Static Brush
  3. Registration Unit
    Flap does not contact with the belt
  4. Paper Tray Unit
    Diameter of Paper Feed Roller is out of standard
  5. Registration Roller
    Diameter of Registration Roller is out of standard
  6. EJ Unit
    Diameter of Flip Roller is out of standard
  7. Head Unit
    Variation of Head due to its poor assembling
Troubleshooting
Step Confirmation and action YES NO
1

Clean the Belt Drawer Unit
Clean the Paper Feed Belt with unwoven cloth moistened with water.

  • Has the image defect been improved?
 End of work Go to step 2
2

Replace the Belt Drawer Unit

  • Has the image defect been improved?
 End of work Go to step 3
3

Replace the Anti Static Brush Unit

  • Has the image defect been improved?
 End of work Go to step 4
4

Print three 25% black patterns

  • See 'Position where oblique unevenness occurs and parts to be replaced' at the bottom of this page and replace the corresponding parts.
 --- ---
5

Replace the Registration Unit

  • Has the image defect been improved?
 End of work

Replace the parts/components to be checked one by one.
6

Replace the Paper Tray Unit

  • Has the image defect been improved?
 End of work Replace the parts/components to be checked one by one.
7

Registration Roller replacement

  • Has the image defect been improved?
 End of work Replace the parts/components to be checked one by one.
8

EJ unit replacement

  • Has the image defect been improved?
 End of work Replace the parts/components to be checked one by one.
Diagonal unevenness appearance place and target replacement parts

A 15.2 mm width diagonal banding due to unevenness in print density appears around the following values.

Cause Distance from leading edge (mm) Target of replacement unit
A4 (Horizontal) A4 (Vertical)
Paper Tray Pick Roller passing 17.2

227.2

Paper Tray Unit

Registration Roller passing

123.2

 333.2 Registration Unit
Support Roller passing

159.8

 369.8 Registration Upper Unit
Entering Separation tab

51.6

 51.6 EJ Unit
Entering Document Ejection EJ Unit Roller

114.8

 114.8
Entering Flip Roller 167.8 167.8

Diagonal Unevenness Position (A4 Horizontal)

No. Outline
(1)

17.2 mm

Print position offset is caused by the load variation that happens when the paper trailing edge passes the MP Pick Up Roller.
(4)

51.6 mm

Leading edge of paper enters the Separation Tab in the Paper Ejection Unit just after the belt.
(5)

114.8 mm

Entering Document Ejection EJ Unit Roller
(2)

123.2 mm

Registration Roller passing
(3)

159.8 mm

Support Roller passing
(6)

167.8 mm

Entering Flip Roller


Diagonal Unevenness Position (A3 Vertical)

No. Outline
(4)

51.6 mm

Leading edge of paper enters the Separation Tab in the Paper Ejection Unit just after the belt.
(5)

114.8 mm

Entering Document Ejection EJ Unit Roller
(6)

167.8 mm

Entering Flip Roller
(1)

227.2 mm

Print position offset is caused by the load variation that happens when the paper trailing edge passes the MP Pick Up Roller.
(2)

333.2 mm

Registration Roller passing
(3)

369.8 mm

Support Roller passing