Canon w8400 wide format printhead bad?

[Penvy]

This wide format printer has not ever shown problems in the past.
We know the head is cleaning and not clogged at all
We know there only 300+ prints on the head.
Turned off the ink monitors nag
changes the bk ink to mbk a few times
have full ink tanks and cleaned many times

I know that the print test will print all colors
but bk
it will clean and we see a lot of ink wasted
this is way too soon to just replace the P head $500

There is a thermistor in the pcb board for over heat protection
I have read many tech's replacing them with no results.
I have done a the wipe of all settings
did not do the update firm ware

just will not print bk
I think the by turning off the ink monitors and changing to mbk and back
somehow has turned off the black from printing.

The print did not get much use for a about 4 Mo turned off, but the clean cycle went through a lot of ink when you turn it on many times.

Its the b1350 head.

I know that dry firing will do that but the cleaning looked as if that was not the problem.
and the overheat protection should kick in.

I know that the easy answer is to replace the head and see.
$500 these days is a lot to find that is not the problem
I have gone thru the service manuals for any lead .


Is there something I have missed?
just looking for some ideas on this
thanks

[Kapten]

[Penvy]

Will look into the firmware up date
The head is clean.
I soaked the bottom in hot water and the ink flows out very well in a paper towel
leaving each color and you can see the "strip" of each color and used compressed air can tube to ck each nozzel color.
I have done this many times with other color printers and really brought back the heads.
Yes you do need to keep the printer running at least every few days.

just the BK that wont print at all!.
I think the switch from BK to MBK and turn off the ink monitor
did something.
Also when you DO turn off the ink monitor I THINK it sets the "chips"
on each color the not be able to return back to where the ink will show.

After much research these chips are a "one time use" ship.
they cant be "reset"

BUT the color should at least print
Keep in mind that this head ONLY has 300 prints on it.

I was thinking that the PCB board that controls it might of had a thermistor on it for each color and the black might of "dry fired" and blown that one thermistor.

The sensors should have stopped this and I had now warning code

Thanks for your help
please respond for any ideas you might have with this info

[Oze]

The latest info from Canon is that before you change a printhead you Must:
:Upgrade system software
:Check or replace the maintenance cartridge
:supply a full set of replacement inks

[Penvy]

Thanks OZE,
The Firmware is 2.15 and thats what I can find on Canons site.
The Maint Cart is new
but all if the inks are almost new(full) and there not cheap X6 $$
good grief Canon has no Idea what they cost to the customer
means at all.

The cleaning just fills up and wastes a LOT of ink for nothing.
The big question here is why Just the BK wont fire.
2013 turn power off error.
It seems like the BK is flowing through the head on cleaning just fine.
But when the nozzle ck starts up and goes thru the test fire of each color the Bk just seems to dry fire.

Do that enough and the ink will "cook" in the nozzle and clog
and you get the shut down error on the overheat sensor.

This is a real tech problem to solve and its as if just the BK is turned off.
But to just change all inks?

WOW...thats $$$$ and with the head and inks over $1000.

The entire printer is only $2500....
Yeah I know I sound cheap but what would you do!

Being here at this site with some of the best tech's is a blast.
I always have the tough ones thats why I come here!.

I would like to know the sequence of why the BK and MBK cant change after the ink monitors were turned off.

All you have to do at start up is to set the error on the ink.
SO what canon is saying is that if you have to turn off the ink monitor to at least run the printer your screwed and you cant turn them back on????????..
Again WOW!.

Its the Bk that is what is not working and even with w MBK that was new cant change back to BK.
The question is .......does the W8400 just not work at all with the BK turned off.
is there something in the software to do that.
Put in a new BK and it will fire?

something to ponder and ask why you cant use the printer with the ink monitors off..

any help again thanks guys

[bobbyboy1948]

No black printing from Canon W8400

have you resolved this problem? I've just acquired a used Canon W8400 & it just refuses to print black, either a printer dump test or a text document in MS Word. Grey is OK but straight black wont print.

I've just replaced the printhead in case it was the problem, got error E02820 Adj failed, but still black will not print. Any ideas?