Black Streaks In Sub-Scanning Direction/Abnormal Noise (Gear Teeth Chipping Sound) From Waste Toner Drive Ass'y; Black Lines: Corrections Against Cleaning Failure By Cleaning Blade - Canon ImageRunner iR8500 Series Service Manual

1. Check the version of DCON ROM.
The control sequence of the drum heater has been changed on Ver.3.01 for iR105 and Ver.30.06 for iR8500/7200.
2. Check whether the cleaning blade has not exceeded its life of five hundred thousand sheets.
3. Check whether the cleaning blade is installed in a correct orientation, where the numbers can be read at the edge of the blade.
4. Check whether the appropriate cleaning blade is used:
For iR105: Part Number FA9-3878
For iR8500/7200: Part Number FB6-2720

15.2.2.3.2 Black streaks in sub-scanning direction/abnormal noise (gear teeth chipping sound) from waste toner drive ass'y

iR8500 / iR7200 / iR105 / iR85
Symptom
Black streaks in sub-scanning direction/abnormal noise (gear teeth chipping sound) from waste toner drive ass'y
Cause
Some gears in the waste toner drive ass'y are scraped off because of a long-term use and thus are unable to drive the waste toner cleaner ass'y. This
deactivates the magnet roller coming in contact with the photosensitive drum, leading to black streaks in sub-scanning direction or gear teeth
chipping sound from the waste toner drive ass'y due to inferior cleaning.
Field Remedy
This symptom can occur if the page count of the machine has reached about three million sheets.
Visually check whether the magnet roller is rotating during operation as follows: Open the front cover and remove the process unit cover. Then,
insert the door switch actuator in the door switch ass'y and start a copy operation.
If the magnet roller is not rotating, there is a possibility that gears have been scraped off. So, replace the waste toner drive ass'y, or the gears.
Waste toner drive ass'y (Parts Catalog Fig. 280): FG6-7328
28T/48T gear (Fig. 280-13): FU3-0414
36T gear (Fig. 280-14): FU3-0415
36T gear (Fig. 280-15): FU3-0416

15.2.2.3.3 Black lines: Corrections against cleaning failure by cleaning blade

iR8500 / iR7200 / iR105 / iR85
Symptom
Black lines: Corrections against cleaning failure by cleaning blade
Explanation
Cleaning failure can occur under the several conditions described below. If your case match either of them, make the appropriate corrective actions.
* For related information, black banding phenomenon is referred at the end.
Field Remedy
[Condition 1] Under high temperature/low humidity, and making duplex copy frequently
[Cause] Agglomeration of toner at the edge of the cleaning blade
[Reason] During continuous duplex copying, the temperature of the drum surface becomes higher than usual because of heat from the paper which has
passed through the fixing ass'y. This will cause waste toner at the edge of the cleaning blade to agglomerate and lift up the cleaning blade, resulting in
toner slipping.
[Corrections]
Change the setting in the 'Drum cleaning enhancement mode' (In service mode [COPIER>Option>BODY>DRUM-CLN]). The drum rotation will halt
during copying, thereby recovering the cleaning performance of cleaning blade.
Setting 0 through 2: A higher setting provides stronger effects.
Setting 3: It will operate as in the case of '2' under normal circumstances and as in the case of '0' (default) under high humidity environment.
[Condition 2] Immediately after turning the power ON (e.g. first in the morning) or low temperature, and making simplex copy frequently
[Cause] Low elasticity of the cleaning blade
[Reason] The drum heater is turned OFF during simplex copy and furthermore the temperature of the drum surface is hard to warm instantly just after
turning the power ON. In such a case, the elasticity of the cleaning blade remains low, resulting in toner slipping.
[Corrections]
1. Upgrade the DCON ROM as designated below:
iR8500/7200: Ver.10.08 and later
iR105: Ver.3.01 and later
(Change: When making simplex copy, the drum heater is always turned ON.)
2. Turn on the drum heater at the back (inside) of the machine. This will keep the cleaning blade soft and enhance the cleaning performance even first in
the morning.
[Condition 3] Drum unit and cleaning blade have exceeded the limit of periodical cleaning interval (half a million)
[Cause] Scratches on the cleaning blade
[Reason] As the drum surface gets soiled, minute contaminants are likely to adhere to it. They will scratch the cleaning blade, causing black lines on the
image.
[Corrections]
Make sure to perform periodical maintenance every half a million sheets. The drum surface and the cleaning blade can be prevented from scratches.
* Related information about black banding phenomenon
[Condition 4] Making a single output of document having low image ratio frequently (especially with printer model)
[Cause] The cleaning blade is turned up.
[Reason] In a single output, the period of no toner on the drum surface is longer than during continuous printing. This will increase the coefficient of
friction between the drum and the cleaning blade, making the blade easy to be turned up.
[Corrections]
Change the setting in the 'Black band increase month mode for January through December' (In service mode [COPIER>Option>BODY>BK-BD-1 through
12]). Forming the black band on the drum surface will decrease the coefficient of friction between the drum and the cleaning blade.
Setting 0 through 3: A higher setting provides stronger effects.
** FYI
Chapter 15
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0002-6220
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