White Lines Appear In Sub Scanning Direction On Solid Black And Halftone Images: Dust On; Partially Blank/Streaked - Canon iR4570 Series Service Manual

Chapter 14
- iR3570/4570
intervals of about 6.3 mm
To facilitate a check, use a halftone test pattern.
<Remedy>
Replace the main motor.

14.2.1.2 Partially Blank/Streaked

14.2.1.2.1 White lines appear in sub scanning direction on solid black and halftone images: Dust on

top cover of Developing Assembly
0008-3408
iR2270 / iR2870 / iR3570 / iR4570
[ Inspected by Canon Inc. ]
Description
As a result of inspection, it was found this symptom occurred because the laser light was intercepted by dust on the
top cover of the developing assembly. If the symptom occurs, remove the developing assembly and clean its top
cover referring to the Service Manual [Maintenance and Inspection > Cleaning > Cleaning the Developing Assembly
Spacer, Feed Guide, Dust-Blocking Glass and Fixing Inlet Guide].
14-6