Weird remaining ink reading error on 3880

[AFairley]

I was printing this morning and got the signs of a bad head clog - banding, posterization - that started in the middle of the print.  I ran a nozzle check, and the PK channel was completely out.  So I did a head cleaning and no improvement at all.  I figured there was a total block in the ink line or a pump failure or something dire like that.  I had a new PK cart, so I swapped it in, even though the old cart was reading 1/3 or so full.  Everything was fine after that.  The old cart I removed is so light, I believe it is bone dry, which would explain nothing printing on the check.  Go figure.

[BarbaraArmstrong]

The exact same thing has happened to me TWICE now on the 3880.  In each case, the PK channel was showing much more than 1/3 full, but a nozzle check showed absolutely nothing coming through on that channel.  I tried two power cleanings separated by an overnight rest, with no result.  Than swapped in a new PK cartridge.  The old one felt like a feather, obviously empty.  I think I needed to run another power clean or two, each of the two times this has happened to me, to get the PK channel to show up on the nozzle check and show a full flow of ink.  I think I must be experiencing a mis-read of the ink remaining in the cartridge, such that it runs dry with no forewarning and then takes a new cartridge and some oomph in the form of a power cleaning or two to get it running again.  You are not alone in this experience.  And my memory of it is good because the last time was just this past week.  --Barbara

[AFairley]

I cracked the cartridge and yes, the ink pouch inside was completely empty.  The thing that's particularly aggravating is that usually you can print to the end of a cartridge, the printer just stops printing in the middle of the print and if you swap the cartridge without too much delay the print will continue with no ill effects.  With this error, the printing continues without any PK ink being laid down, ruining it.

[Farmer]

Do you leave the printer turned on all the time or do you turn it off periodically?  Have you had any power failures?  Do you use a UPS?

[BarbaraArmstrong]

I have left a number of printers on full-time over many years without difficulty.  And there have been no power outages or other irregularities in the power supply to attribute this recent problem to.  I know some "irregularities" aren't particularly noticeable, but I've not been aware of anything. --Barbara

[AFairley]

Turn off when not printing (only print on weekends), no power outages that I can remember.  Only variable for me would be that i installed 3/4 PK full cart instead of new when I got the printer and first set it up.

[Farmer]

Best practice is to swtich off when not in use, this forces a write back to the carts and also protects them against surges or brownouts.  That said, sounds in this case like it's faulty carts.

[BarbaraArmstrong]

At least we got the use of the ink in them! --Barbara