9900: Abrupt and Complete Loss of LC

[John Caldwell]

What is suggested by the following Epson 9900 sequence:

1) Print a 100% clear nozzle check after machine is booted, the machine having not made a print in 72 hours. Recent behavior, prior to last printer shutdown, has been trouble free with very rare partial nozzle clogs. Ambient conditions wrt humidity and temperature should be ideal.
2) After printing the above 100% clear nozzle check, a second nozzle check is printed for good measure.
3) LC is completely absent on second nozzle check, only 30 seconds following prior perfect LC nozzle check. All other channels are again 100% clear.
4) Test prints that substantially exercise LC channel are fully blank in LC areas.
5) Further check patters are again 100% vacant in LC channel, yet 100% intact for other ink colors.

Clearly this does not point to a clog in the traditional sense. What does this point to, if you have a guess? Can a pump be abruptly lost yet have it affect only one half of a shared ink pair?

Many thanks,

John Caldwell

[hugowolf]

Did you do a PK/MK or MK/PK switch at any point during this? I have had completely blank, seeemingly unrelated, colors after black switches.

Brian A

[Peter Le]

          I think what is happening is you pulled air back up into the head ........ It just happened to me. Printing or even regular cleans don't seem to force enough ink to clear the air. A power clean on the regular menus worked for me........supposedly a power clean does not fire the pezo's  in the head.........draws a vacuum and pulls a far amount of ink through the head and expelling the air.

[Garnick]

Hi John,

I've certainly had my share of issues with the 9900 in various ways.  It has been working well recently, but while printing a fairly high volume of 11x14's a few days ago the last print showed signs of a complete Y dropout.  Of course the nozzle check confirmed that and I did a regular pairs clean.  Next nozzle check showed a few bars, but barely there.  Ran a full colour print to activate all nozzles and another pairs clean.  Nozzle check showed a few more bars.  Another full colour print and a power clean and then the nozzles were all back in working order.  I think it definitely has something to do with the pressurization system at that point, but no clear way around it.  I generally don't run any more than 3 or 4 cleaning cycles in succession, always followed by a full print.  If that doesn't clear the problem I let the printer sit idle for a while and try again.  If this issue occurs late in the day I turn the printer off and leave it overnight.  The theory is that by powering down and then back on after a period of time it re-pressurizes the carts.  I don't know if that is actually the determining factor, but it seems to work.  Could be strictly coincidental, but if it works that's irrelevant.  If none of this works the last resort is to call Epson Service.  Or, if it's under warranty that would be your first choice.  Hope it works out quickly John.

Gary   

[John Caldwell]

Thanks for everyone's interest. I'll give this some cleaning cycles, maybe $100 of ink's worth, and then let Epson deal with it.

Thanks again.

John

[Wayne Fox]

Usually pairs power clean resolves it.  It might also indicate a bad damper or capping station which is letting the air pull back in.