IP4300 - PGBK not printing: Clogged head or what?

[Sherden]

I've just finished refilling the carts, the printer is doing some cleaning cycle by itself and emptied cyan, yellow and magenta carts (this afternon the first time I pulled them out they were still at 15%).

I hoped it was only a problem of empty cartridges but no luck . So now, apart from the PGBK missing, also the cyan is becoming an issue

By the way, is an erratic ink level indicator (the cartridge where about to empty and the software still showed them full or 3\4 full)an electronic damage sign also??

 

[PeterBJ]

An electronic damage to the printer could cause the problem with erratic ink levels. But it could also be caused by the chips on the cartridges. Ink leaking out from the cartridges could also cause this wrong indication. The chip doesn't measure the ink level, it stores a value calculated by the printer, so leaking will cause the ink level to go wrong as leaked ink is not calculated.

Are the cartridges Canon OEM that you refill and reset? I have experienced an after market cartridge run out of ink, even if the ink level indicator showed 50% left. If you refill, then what brand of ink do you use? The clogging of pigment black might be caused by bad ink.

Leaking ink can cause problems. I have lost a print head in an iP4200 due to a leaking bad quality after market cartridge. The leaked ink crept under the foil on the underside of the print head and created a short that took out a quarter of the yellow nozzles, causing an error similar to your cyan problem, but in yellow instead.

If a new cleaning of the contacts on the print head and in the print head carriage doesn't make the cyan problem go away, then the print head is damaged, and the logic board might also be damaged, so replacing the print head is a gamble, and sadly I cannot tell you the odds for success.

The parts number for the print head is QY6-0061 if you want to search the web for one.

 

[Sherden]

I am using the original OEM Canon cartridges refilled with InkTec ink and resetted with a cartridge resetter.

The first time I took away the printing head (in June) to clean it I took a few pictures:



Could this be similar to the short you experienced? The leak is on the side where the CLI pins are

And here is the underneath



It was pretty dirty of black ink (PGBK I suppose). Is it normal for the printhead to get so dirty?

This morning picture: it looks like little bit cleaner

 

[PeterBJ]

It looks to me like there has been a serious leak of pigment black ink. Print heads should not get that dirty. This might have caused electronic damage.

How do you refill your cartridges?

If you are using the top fill method it is vital that the refill hole is sealed properly, else the cartridge will leak.

If you are refilling using the "German" or "Durchstich" method, then overfilling can cause leaking.

You can test a refilled cartridge for leaking by placing it in a shallow tray or similar for at least ten minutes. One or two drops of leaked ink is OK, but the cartridge must not continue to leak.

 

[Sherden]

I use the German method and I made a mess last time I refilled the PGBK before experiencing the issue. Probably I overfilled the cartridge because it began to spill ink everywhere so this could explain the leak in the picture

 

[PeterBJ]

Like water and cleaning fluids ink residues are also electrically conductive, so if they are left in places where they do not belong, they can cause a short circuit or leakage current that can ruin the print head and the logic board.

The places that are specially dangerous are behind the ribon cable and the circuit board. This is the reason it is very important that a cleaned print head is completely dry before it is put back into the printer.

Here is an excellent instruction by pharmacist, showing how the PGI-5/CLI-8 cartridges are refilled properly using the "German" method.

Edit: If the plastic ball at the top of the cartridge was removed for flushing, it is vital that the hole is sealed properly, like when the cartridge is top filled. Good silicone plugs to seal the hole are available.

 

[Sherden]

that hole is untouched

I'll try again to clean it with pharmacist's fluid but I fear that the head could be electronically damaged. This because last time I cleaned it water flowed through easily but on the other hand I was able to get the PGBK back again even if for two prints only. I'm really puzzled

 

[Sherden]

Just started cleaning the head again with W5 . I will keep you posted

 

[turbguy]

Like water and cleaning fluids ink residues are also electrically conductive, so if they are left in places where they do not belong, they can cause a short circuit or leakage current that can ruin the print head and the logic board.

The places that are specially dangerous are behind the ribon cable and the circuit board. This is the reason it is very important that a cleaned print head is completely dry before it is put back into the printer.

Here is an excellent instruction by pharmacist, showing how the PGI-5/CLI-8 cartridges are refilled properly using the "German" method.

Edit: If the plastic ball at the top of the cartridge was removed for flushing, it is vital that the hole is sealed properly, like when the cartridge is top filled. Good silicone plugs to seal the hole are available.

Do you have any conductivity/resistivity measurements on ink? Note that ultra-pure water is non-conductive....

 

[PeterBJ]

Ultra-pure water is an insulator, ions in less than ultra-pure water makes it conductive. Resistivity is a quality measure for demineralized and distilled water. But ink is a mixture of pure water and other things, of which some seem to make the pure water conductive.

A simple test to prove ink is conductive is to touch the test probes of a multimeter set to measure resistance, preferably in the Megohm range, to the ink outlet of a Canon ink cartridge. This proves ink is conductive. Note that the resistance drops when you press the tips of the probes harder against the ink outlet, due to a larger area touching the probes.

The drive logic in a Canon print head operates at 3.3 V, and the inputs of the logic are high impedance, in the Megohm range. The voltage on the input of a CMOS logic device must never go above the supply voltage or the device could be damaged.

The print head also has a much higher supply voltage of 24 V for the nozzle heaters. A small leakage current through a high leakage resistance, caused by spilled ink or other liquid, from a 24 V conductor to a 3.3 V logic input could easily cause the voltage on the input terminal to exceed 3.3 V, damaging the logic circuit. A damaged logic circuit could be the cause of the burn-out of print heads by constantly turning on several nozzle heaters.

The resistances I measured were in the few hundreds of kiloohms to a few Megohms range, so this rules out the ink causing burnt holes in a ribbon cable by directly short circuiting the 24 V supply. Instead I think the constant turn on of nozzle heaters, that are only designed for pulsed operation, by damaged logic circuitry is responsible for the burn out. Here is a photo of a damaged print head with burned holes in the ribbon cable: