Shift in Yellow in Canon C3220

[aoab50]

I have a Canon c3220 with imagepass c1 controller, lately there has been a shift in the yellow color, I don't know how this happened. I changed the yellow toner but it didn't work, I cleaned the belt that transfers the papers but nothing happend.
This problem happens when I print from the computer and also when I copy with the controller turned off, so I guess the problem is not from the controller.
I'll be very grateful if someone could help me.
below is a scanned sample:

canon c3220 yellow shift.jpg

[teckat]

I have a Canon c3220 with imagepass c1 controller, lately there has been a shift in the yellow color, I don't know how this happened. I changed the yellow toner but it didn't work, I cleaned the belt that transfers the papers but nothing happend.
This problem happens when I print from the computer and also when I copy with the controller turned off, so I guess the problem is not from the controller.
I'll be very grateful if someone could help me.
below is a scanned sample:

canon c3220 yellow shift.jpg

=================================
The following factors can displace images of individual colors:
• displacement of the photosensitive drum caused by replacement of the drum unit/toner container
→ displacement in sub scanning direction
• displacement of laser path caused by replacement of laser unit
→ displacement/angle in main scanning direction
• displacement in laser path length caused by changes in temperature inside machine
→ variation in magnification
To correct the discrepancies in images, the machine executes corrective control for image position; it detects displacement in color by forming a pattern of a specific color on the
transfer belt and reading it against the correct position.

Printer uses YELLOW as Patch Reference
u can also remove and clean Patch Reader----------------(Reader is for individual color patterns) u can watch the patch laydown on ITB> remove small cover over ITB> power up printer to view----------
Y pattern is used as the reference. The machine identifies the degree of color displacement in sub scanning direction with reference to the timing at which other color patterns
are checked after a check on the Y pattern.
If the timing is not correct, the machine will try corrects the laser write start timing in sub scanning direction.



see attach/ + run a PG 6 GRID TEST IN SERVICE MODE/
PG 6.JPG


if Yellow is only issue suspect Yellow Laser Cam is out of alignment/ or Yellow Drum



iR3200-3220 Color Displacement.pdf

[SAZ911]

Hi Guys,

Thought id'e throw in my two cents.

I think that you have the same issue with all the colors, If you look at the "PANTONE DIGITAL COLOR" logo at the bottom of the sample page, you will notice that the black and Magenta don't line up either.

Print a PG-Type 10 and you should be able to notice if they are all shifting. Also you will notice the shift if you do a Gradation Adjustment, you'll notice on the right edge of the colors printed, that they don't line up vertically.


If So.....
Check the state of your ITB Assy, the bearings on the ITB Assy are probably dirty and need a good clean. I found that cleaning them thoroughly and oiling them gets them back into shape, also replacing the whole damn thing (ITB Assy) would be ideal.

I have had this same problem from the IRC2620, 3200 and even the IRC4580i....

Hope it helps,
Cheers,

[aoab50]

Thanks alot Teckat and Saz911. I'm very grateful for your help.
I ran a PG 7 test, there is an equal shift between (black & cyan) and (cyan & magenta) but the shift between magenta and yellow is more. please see the attached test PG 7.
test no. 7.jpg
can I fix this problem by changing CCD variables in service mode?

[teckat]

Thanks alot Teckat and Saz911. I'm very grateful for your help.
I ran a PG 7 test, there is an equal shift between (black & cyan) and (cyan & magenta) but the shift between magenta and yellow is more. please see the attached test PG 7.
test no. 7.jpg
can I fix this problem by changing CCD variables in service mode?

Read off

On a pg6 GRID test print , u can see miss-registration directions_ as in paper feed or Crossfeed.

Pdf shows some steps to take, there is no quick fix.
Starts with some general inspection to cleaning to checking

[copier tech]

Any colour shift issue on this series I've found to be related to the ITB.

A simple test is to remove the transfer cleaning blade & run a test print again, if all colours are aligned (ignore & other quality issue) then you know the ITB belt is slipping a tiny bit (the cleaning blade can act like a brake)

Usually removing & cleaning the inside of the belt & the large rubber drive roller will cue the issue.

However if the belt is old I would replace it.

[aoab50]

I left my machine since the last time I replied to this thread, I didn't have time then.
recently I tried to fix my machine again, but I noticed that this problem occurred when I replaced the defect yellow drum unit, and the label of the new one is different from the others. I think the problem in my machine is due to drum unit change, just Like Teckat said, because it is in sub scanning direction. But Teckat didn't mention how to fix this problem.
I've attached test type 6 and 10, but I had to crop them to reduce the size of files.
test #10_2.jpgtest #6_2.jpg

Thanks for your kind help.

[teckat]

I left my machine since the last time I replied to this thread, I didn't have time then.
recently I tried to fix my machine again, but I noticed that this problem occurred when I replaced the defect yellow drum unit, and the label of the new one is different from the others. I think the problem in my machine is due to drum unit change, just Like Teckat said, because it is in sub scanning direction. But Teckat didn't mention how to fix this problem.
I've attached test type 6 and 10, but I had to crop them to reduce the size of files.
test #10_2.jpgtest #6_2.jpg

Thanks for your kind help.

-----------------------------------------------------------------------------------
Correcting Image Displacement

The following factors can displace images of individual colors:
• displacement of the photosensitive drum caused by replacement of the drum unit/toner
container
→ displacement in sub scanning direction
• displacement of laser path caused by replacement of laser unit

→ displacement/angle in main scanning direction
• displacement in laser path length caused by changes in temperature inside machine

→ variation in magnification
To correct the discrepancies in images, the machine executes corrective control for image
position; it detects displacement in color by forming a pattern of a specific color on the
transfer belt and reading it against the correct position.


> Detecting/Correcting Color Displacement in Sub Scanning Direction
The Y pattern is used as the reference. The machine identifies the degree of color displacement
in sub scanning direction with reference to the timing at which other color patterns
are checked after a check on the Y pattern.
If the timing is not correct, the machine corrects the laser write start timing in sub scanning
direction.

>So if your ITB drive gear unit has damaged teeth or ITB sheet is slipping (because of gear damage/worn teeth) over it's internal black rubber drive roller, that could equal a sub scan registration issue.



sub scan is Paper Feed direction

sub scan.jpg


I. Gear Replacement due to color mis-registration in the sub-scanning (paper feed) direction ( this is a know pain in the butt issue, worn teeth on helical gears(////) walk over each other )
1.The 42T gear of the ITB Assembly and the two 42T gears of the ITB Drive Assembly were changed from molded plastic to machined plastic. The gear in the ITB Assembly will be given a new
part number and available as a service part. The gears in the ITB Drive Assy. will now be as follows:
The dowel pin gear is available as a service part and the other gear is now pressed on the Swing Gear Assembly and unavailable as a service part. The entire Swing Gear Assembly must now be ordered.
II. Transfer Belt/Drive Roller Cleaning due to color mis-registration in the sub-scanning (paper feed) direction
1.In a high usage environment, excess toner will accumulate around the inside of the Transfer Belt area especially soiling the Transfer Guides and the Drive Rollers. This will result in color misregistration
by as much as 3mm. Prior to purchasing a new Transfer Belt, it is highly recommended that the special cleaning procedure described below be implemented.

see attachment
iR3200-3220 Color Displacement.pdf

[aoab50]

Thanks a lot Teckat.
I dont think the problem is from the gear assembly, I,ve opened the back of the machine and checked the teeths of all the gears i could see, And the counter on my machine is 20k papers.
I read some other posts about this issue, some recommended clearing dc-con, but it it didn't change any thing at all.
I also cleared mmi and mn con, but still nothing happened.

[teckat]

Thanks a lot Teckat.
I dont think the problem is from the gear assembly, I,ve opened the back of the machine and checked the teeths of all the gears i could see, And the counter on my machine is 20k papers.
I read some other posts about this issue, some recommended clearing dc-con, but it it didn't change any thing at all.
I also cleared mmi and mn con, but still nothing happened.

-----------------------------------------------------------------------------------------------------
did u ever inspect/ replace/celean that Pattern Reader unit


those white slant teeth gears are difficult to view to determine if they are walking over each other ---- when they spin drive> even if two or three are worn it climbs over/

remove the cover to view operation of them> u may even here a slight noise> run some text docs and view belt/& listen/

I remove that gear section without removing the whole motor drive unit (unit is a pain to remove)

tech tip> works on all of those metal cotter pins that need to be in place on a end shaft before u set a gear in place-----

TIP is to use a small amount of chewing gum on metal pin> then slide through hole on shaft>u will never loose another pin