Question about Canon PIXMA MP780 All-In-One InkJet Printer

3 Answers

Canon MP780 didn't report out of ink and now will not pring blanck

I was printing a document and all of a sudden blank pages were coming out. Check the black cartridges and they were both empty but I had received no message that they werw low or empty. Put in two new cartidges and still will not print black. Tried another of the large black cartridges and still no black printing. Tried to print a test page from window and the colors show up in the windows logo but nothing else. Any ideas on how to fix.

Posted by David Minshew on

  • 1 more comment 
  • kaligad Nov 06, 2007

    replaced black cartridge will not print black at all, tried another cartridge still no joy. Switched it off for a few mins to reset and still

  • ionacarr Jan 27, 2009

    The black ink (B3e) will not print. I suspect it is due to lack of use combined with using substitute ink tanks. I am not sure ow to fix this but would like to know if others find the same. Did you use a non canon ink replacement?

  • Anonymous Mar 23, 2014

    new color cartridges, and new large black cartridge, smaller black cartridge is low



3 Answers


I recently had the same exact problem. It seems, as with most electronic machines, its electronic circuitry needs to be reset every once in a while. So I unplugged the machine while still on, waited about 2 minutes or so and then replugged it. It started printing normally. I did take out all cartridges first, but I'm not sure that step is necessary. Give it a shot. It worked for me.

Posted on Jun 13, 2007



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When the machine doesn't register the ink levels it is caused by a faulty PCB. Just keep using the machine, the fault is not worth repairing. With this machine you must use genuine ink or you can have lots of problems and throw the machine away.

Posted on May 28, 2007



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Have you tried cleaning or aligning the heads? Were the first cartridges refills? when an ink cartridge is refilled (depending on the model) the printer needs to be tricked into thinking a "new" cartidge is being installed. You may need to check the owners manual to see if the is the case. I have had to use tape to block off certain contacts, then remove the cartidge and block off another section of contacts, then remove tape all together and re-insert the cartridge.

Posted on Jan 29, 2007

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