Pixma 780 nozzle check problem

[diggerdave]

My Pixma 780 is not printing any colors. When I ran the nozzle check it only printed the top line for the 3eBK cartridge. There's not a hint of any other cartridges trying to print.

 

[ghwellsjr]

You need to see if your purge system is working. Open the cover and wait until the print head stops. Take a flashlight and look off to the right where the print head parks for two black pads. The square one for your color dye inks is easy to see. The rectangular one to its left is more difficult to see but you are not concerned about that one anyway. Take a syringe or an eye dropper or a pinched straw and put some Windex or other window cleaner or just plain water on the square pad to the right. Verify that the liquid remains on the pad for ten or fifteen seconds. It will look shiny from the liquid. Close the cover of the printer and wait for the noise to stop. Now open the cover and look at the pad to see if the liquid has been sucked away. It should look dull and coarse and not shiny like it did before. Post your result for further instruction.

In the mean time, do not remove the print head from your printer or attempt to fix it.

 

[leo8088]

It may be a problem in the purge unit as ghwellsjr suggested. However, unless the purge unit was tampered by someone it is really very unlikely that the purge unit becomes defective without a cause.

On the other hand it is very likely that you have not used your printer for a long time and the nozzles are dried up. The nozzles are clogged. I will not hesitate to unplug all ink cartridges and take the print head out for a simple treatment that may quickly fix the problem. Just make a stack of soft tissue paper by folding a sheet of kleenex (the tissue paper we use to wipe our nose) several folds of sever square inches in size. Drop some water from a faucet to the stack of tissue paper to make it wet. Now you can put the print head on top of the wet stack of tissue paper. You can give it a little pressure on the print head against the tissue paper. You can let it sit on it for a few minutes. Reinstall the print head and all ink cartridges and run a regular cleaning cycles, followed by a nozzle check. If you see some improvement you can repeat it a few more times. Chances are good that it will work perfectly again.

If there is no improvement you have a much more serious problem to deal with. It could be a purge unit that wont purge or your print head is badly clogged. Don't print anything just yet before the nozzle check is near perfect or you can cause damage to your print head. You can try one deep cleaning cycle. If it makes some more improvement you can do another one but no more than two. If two do not fix it more will not do it either. You will need more soaking of the print head. Extensive soaking of the print head will be kind of risky. Personally I will do it knowing perfectly what the risk is. But I know some will say no....

 

[diggerdave]

There is still windex on top of the pad.

 

[diggerdave]

Clogged nozzles sounds likely. I have had my settings set to grayscale for a couple of years.

 

[ghwellsjr]

Since we have learned that the purge unit for your dye ink is not working, we need to find out if the purge unit is working for your pigment ink. Repeat the experiment with the purge pad on the left.

Leo8088 has given you one piece of good advice: don't print anything except for nozzle checks until you fix this problem.

There is no point in doing cleaning cycles while your purge unit is not working because it uses the purge unit to perform the cleaning cycles. And there is no point in trying to clean your print head using any method because it still won't work until you get the purge unit working which is required to get ink to start flowing through your nozzles. Even if you replaced your current print head with a brand new one, it would have the same problem.

 

[diggerdave]

When I opened the printer up to test the rectangular purge pad, the liquid in the square pad had been absorbed. Did I just not wait long enough?

 

[ghwellsjr]

Just repeat the test with both pads. Put Windex on them, close the cover and wait long enough for all the noise to stop. Then open it and look at the pads.

However, since it appears that your purge unit is probably working, the next step is to see if you have good cartridges. Since you have not printed using the dye ink cartridges in years, they may be dried up or empty. Are you using Canon original (OEM) cartridges or compatibles? Do you have some empty cartridges that you can use as cleaning cartridges?

If you have an empty or extra cartridge, turn it upside down and dribble Windex into the ink outlet port until it starts to drip down from the sponge material inside the cartridge. Turn it over on a paper towel and wait until it has stopped dripping. Put it in your printer. You can repeat this for as many extra cartridges as you have.

If you don't have any empty or extra cartridges that you are willing to sacrifice for this purpose, just remove the cartridges in your print head and place a drop of Windex on the small mesh on the print head where the cartridges go and then replace the cartridges.

Put some more Windex on the square purge pad. Do a cleaning cycle. Do a nozzle test.

If you see any printout for the dye inks, repeat the entire process as long as you see improvement.

If you don't see improvement, put some Windex on the purge pad, close the cover, wait for the noise to stop and then unplug the printer without turning it off. This will soak the nozzles without any risk of damaging the print head. Leave it this way for a day or over night.

Plug the printer back in and turn it on. Do a nozzle check. If you see improvement, you can repeat the process of putting Windex on the screens and pad, followed by a cleaning and nozzle check, or simply putting Windex on the pad and pulling the plug and waiting for several hours.

This process will use up your pigment black ink if you do your cleanings from the panel on your printer. It would be better to use the maintanence tab on your printer driver to do print head cleanings for just the colors.

Good luck and let us know how it turns out.

 

[diggerdave]

I cycled through the Windex, cleaning, nozzle check a half dozen times. I was optimistic, but the next 2 cycles got progressively worse. I'm on to plan 'B'. I put Windex on the Pad and pulled the plug.

 

[ghwellsjr]

I thought you said there was no printout for the dye inks--what do you mean by it "got progressively worse"? Is the pigment black ink starting to show clogged nozzles?