Color Bars with Canon s750

[Riebejamen]

My canon s750 printer has been printing color bars only at the top of an image. At first it was only the top 1 1/2" of an image that had horizontal bands of color. Ie, It's suppose to print purple; it prints one line purple, the next line is light purple. The third line is purple, next is light purple. Same with another color 1/4" down. It is suppose to be lime green; it prints lime green, then light, then lime green, etc. This is only for the first 1 1/2" or so, then the rest of the image is fine.
I took out the printer head (the carriage that holds the ink cartridges), and soaked the bottom for little over an hour in isopropyl alcohol. Repeating until the alcohol stayed mostly clear. I wiped the heads carefully with q-tips and set it aside to dry. Several hours later, I reinstalled the part and the 4 cartridges. I've done cleaning and deep cleaning several times. Also did nozzle check and print head alignment several times. Now black will not print, and I still have banding.The black ink prints on print head alignment, but the yellow does not. I tried printing a test page with black text, and there is no ink on the page. I set up another test page with blue and red text, which printed fine. The black cartridge was replaced 2 weeks ago and until I tried to clean the heads, worked fine. I am stumped what is wrong and what to do next. Many Thanks!

 

[ghwellsjr]

The only thing you should be printing while you are having these problems is a nozzle check. Alignment only works when all the nozzles are working. The important thing is what does the nozzle check look like? It sounds like it doesn't print any black but what about the three colors, cyan, magneta, and yellow. Do they print solid bands of color?

I think you probably damaged the electronics that control the black printing. This is very common when cleaning the print head outside the printer and not allowing two days for everything to dry out inside the print head. I've done it and not only damaged the print head, it also damaged the printer.

 

[Riebejamen]

I did another nozzle check today, Monday 5/31. The black does not print with the small color grids at the top of the page. But it does print mostly at the second section, which has the bars of color. The yellow is lime green. One of the "solid" black boxes has banding; 3 rows are black, 3 rows are grey.
When I soaked the print head, I let it sit to dry overnight (I live in AZ, the weather is warm, and things tend to dry REALLY fast). And if the print head were damaged, wouldn't all the nozzles have trouble, not just the black? And why is there color banding?
Thanks!

 

[ghwellsjr]

Since I have never seen an S750, I can only guess what the nozzle check is supposed to look like, but if it is typical of Canon printers, it should look something like this except that you won't have the BK at the bottom of the nozzle check:

You mention purple and lime green which should not be on the nozzle check. If you see these colors, it indicates that the cyan ink is leaking into the magenta (making purple) and into the yellow (making lime green). It may actually be contaminating the cartridges in which case you should replace them. Then you can see if they get re-contaminated and if they get mixed on the nozzle check. If there is a leak inside the print head, you're going to have to buy a replacement print head which should solve all your other problems. It's going to be expensive to buy three more color cartridges just to find out, plus the print head will set you back over $100.

It is also possible that the leak is occuring outside the print head, on the purge pad where the print head parks.

One other thing: The black grid lines at the top of the nozzle check are produced by the wide pigment black ink cartridge. All the other images on the nozzle check are produce by the three color dye ink cartridges. The blocks to the left of the bars are made with combinations of the three color dye inks so that they look black but they are not made from the black cartridge.

 

[Riebejamen]

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Here is what my nozzle check looks like.
I am sorry I wasn't more clear. The banding started with the printing of lime green and purple business cards. I did deep cleaing and cleaning from the maintainance window. That did not solve the problem. The black was working fine until I soaked the printer head in isopropyl alcohol and then let it dry until the next day.
I reinstalled the printer head, and printed a section of the business cards. The black was missing from document and the banding was still there. I ran a nozzle check, and an alignment. Much, but not all, of the black test images were missing, or only had part of an image. (this web address has what a s750 nozzle check should look like: http://www.inkjet-laser.com/cleaning-the-printhead-nozzle-check-pattern-canon-s900s820s750s520.html). I deep cleaned again and let the printer sit until today. I ran another nozzle check, which is above. The black is intermitant on the test, and the black block in the center shows banding. (The yellow grid shows as lime green.) What causes the banding?
Thanks!

 

[ghwellsjr]

The link for your first image is messed up--you need to fix it. You don't need to use the Thumb link for these small images, just use the Image link.

It looks like the nozzle check prints both a nozzle check and the results of the alignment. Your second link is so faint and low resolution that I cannot tell what it is. The large grid pattern at the top is for the wider pigment black ink. Below that are several smaller grid patterns but I cannot tell how many there are nor what their colors are. Do you see at least one of magenta, cyan and yellow? How many grid patterns are there in total?