Image Defects - Canon CLBR 460ps Service Manual

II. IMAGE DEFECT
If the cause of the malfunction is identified to "image defect" by the malfunction diagnosis flow-
chart (Figure 4-1-1), find out the factor and clear the problem according to the table shown
below.
Defects
I-1 Light
I-2 Dark
I-3 Completely Blank
I-4 Allblack/solidcolor
I-5 Dots in Vertical Lines
I-6 Dirt on Back of Paper
I-7 Dirt
I-8 Vertical Lines
I-9 White Vertical Lines
I-10 Horizontal Lines
I-11 White Horizontal lines
I-12 Color missing
I-13 Blank Spots
I-14 Poor Fixing
I-15 Image Distortion/Color Mis-registration
I-16 Image Smearing
I-17 Image Misplacement
[ 2-1 ] Light
<Possible causes>
1) The image density is not adjusted correctly.
Action: Adjust the image density by operating the external device.
2) Execute a test print. Open the drum cartridge drawer during toner development (16 seconds
after pressing the test print switch). Remove the drum cartridge. If the toner image on the
photosensitive drum surface is faint, go to step 9).
3) Poor contact in the primary transfer bias contacts of the ITB unit and the high-voltage PCB.
Action: Clean the primary transfer bias contacts between the ITB unit and the high-voltage
PCB. If the problem persists after cleaning, check the contacts and replace any
deformed or damaged part(s). If the contacts are slipped off, adjust them correctly.
4) Poor contact in the secondary transfer bias contacts of the secondary transfer roller and the
high-voltage PCB.
Action: Clean the secondary transfer bias contacts between the secondary transfer roller
and the high-voltage PCB. If the problem persists after cleaning, check the contacts
and replace any deformed or damaged part(s). If the contacts are slipped off, adjust
them correctly.
Table 4-2-1

Image defects

Additional explanation
Output very light image.
Output very dark image.
Output no image.
Output all black or solid colored paper.
Output white dots on the paper.
Output dirt on the back of the paper.
Output dirt on surface of the paper.
Output vertical lines.
Output white verticallines.
Output horizontal lines.
Output white horizontal lines.
The specified color was not printed.
Output image with blank spots.
Output image with poorly fixed toner.
Output distorted image or mis-registered color image.
Output smeared image or dirt on image.
Image is not placed correctly.
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