ip4000 Nozzle Checks (Std and Extended) missing a portion of cyan band

[BShark]

The standard nozzle check looks normal except that on the top 6C row (dark cyan) the top half is dark cyan but the entire bottom half is light cyan. (Should be all dark.) The second 6C row (Light cyan) is normal. Very uniform colors so clogged jets does not seem to be the problem.

Then the extended nozzle check printout shows 4 cyan grids at the top. The top 2 cyan grids should be dark cyan and the bottom 2, light cyan. The second dark cyan grid is missing its bottom half. That is, the top half of this grid is dark cyan, and the bottom half is blank. Other than that, all the grids are normal.

Any ideas what this points to?

Thanks for your help!

 

[ghwellsjr]

It points to an electrical problem in the print head. You will need a new print head to fix the problem but they are no longer available from Canon. You might be able to find one at a local authorized Canon repair center. There are some on eBay both refurbished, used and new. Another option is to find a used printer on craigslist that uses the same print head which you might be able to get for $20 or less. If you look at the eBay listings, they will tell you which printers use the same print head.

 

[BShark]

Thanks for your feedback. I was afraid it might be an electrical problem.

However, I've seen in some of your other posts about electrical problems developing because of ink leaking onto the contacts of the print head. Could this be a reason for what I'm seeing?
Thanks again for your help!

 

[ghwellsjr]

I've warned against letting ink or other liquid get inside the electronics inside the print head. Do you have reason to believe something like this happened in your case? I've seen the kind of electrical problem you have just spontaneously happen to a working printer for no apparent.

 

[BShark]

I had an ink pad alarm about 6 months back. I thoroughly cleaned the ink troughs where the pads sit, and cleaned the print head as well. (At that time, I also had a little clogging which affected my prints a little.) After that cleaning, print quality was fine until this.

I guess I'm wondering if wiping off the print head contacts or the like would help clear up the missing jet outputs?

One other thing I wondered about these 2 missing cyan bands: Does the print head use different jets for cyan output depending on what direction the print head is traveling? Or are the same jets used for cyan output regardless of direction?

The reason I ask is that all the nozzle check print outs are perfect for cyan except for the 2 missing bands I described in my first post. If these missing bands use the same jets as all the other cyan bands, it seems to say that those jets are fine, but they just aren't firing in one direction. Is this how it works? (If so, I guess that still comes back to an electronics problem again.)

Thanks!
--- B

 

[BShark]

Anyone have any further thoughts on these 2 questions?

Many thanks!

"I guess I'm wondering if wiping off the print head contacts or the like would help clear up the missing jet outputs?"

"Does the print head use different jets for cyan output depending on what direction the print head is traveling? Or are the same jets used for cyan output regardless of direction?"

 

[The Hat]

Anyone have any further thoughts on these 2 questions?

Many thanks!

"I guess I'm wondering if wiping off the print head contacts or the like would help clear up the missing jet outputs?" Its too late for that.

"Does the print head use different jets for cyan output depending on what direction the print head is traveling? Or are the same jets used for cyan output regardless of direction?" There is only one set of nozzles for the cyan and by your description only half of them are firing correctly.

So I agree with ghwellsjr expert opinion above, its time for a new print head..

 

[BShark]

Thanks, to you both. That sound you hear is me biting the bullet!
--- B

 

[ghwellsjr]

But to answer your question about nozzle used in different directions, yes, each nozzle is designed to work in one direction of the other. The nozzles are aimed in the opposite directions in which the head is traveling so that the horizontal motion is taken out and the droplet of ink can fall directly down onto the paper. The alignment process is to control the timing so that the printer can lay down droplets fired in one direction exactly on top of the droplets fired in the other direction. See the posts starting at #19 of this thread for more information:

http://www.nifty-stuff.com/forum/viewtopic.php?pid=10642#p10642

 

[BShark]

Ah-ha! So there's a whole bank of nozzles not putting out at all.

Thanks again. I just put in an order for a new print head.

(BTW, you might be interested to hear what this on line seller told me when I spoke to him over the phone. He said that, yes, my print head (QY6-0049) was discontinued in December, but he said that there must have been still some demand such that Canon has not completely shut down production of these and he is still getting them from Canon. The seller was PrintHeadExpress.com.)

--- Brian