L1800 - all ok, but not printing

[Stuart21]

My L1800 has developed anew problem; does everything correctly, cleans heads propery, but will not print anything - test print or any other file. No ink whatsoever. Have changed heads and main boards but all the same.


Does the printhead number need to be entered into the rom?

 

[Ink stained Fingers]

do you get any error code ? - Not printing - does it mean that the printhead is moving but does not put any ink onto the paper ? or ? do you have a service manual ?

 

[Stuart21]

Thanks, ISF!

Yes, it does everything as it normally should - only thing different is that not one jet is firing! Yes, have looked through the service manual for L1800 and 1390 - cannot see this fault -

Have swapped printheads (now on a new one) also main boards - no difference-

I am using a Mac, so we don't get error codes, except 'Fatal Error'

;-(

 

[Ink stained Fingers]

You may use the WicReset utility, the status function is reading the last 5 error conditions from the printer, you may get something this way. Could it be that there is a connection problem with the flat cable connector to the printhead, e.g. missing ground, some signal which is so basic that it is not controlled by a sensor, some spoiled connector pad, misalignment of some sorts , it's just guessing.

 

[Stuart21]

Thanks ISF, have now used WICreset - by shuffling printheads and main boards have got to a zero fatal error.

Goes through the motions of printing, but absolutely no ink printed.

A couple of weeks ago I was having trouble with my computer - it would not restart, so I installed a new UPS to keep it up and running. However I noticed that I was getting a fair amount of stray electricity - felt like the about 50 V of a telephone line - so I changed the printer to powered by the UPS. Since then, had no print. Even changed back to old UPS, still no print.

Could it be the power board?

TIA,
Stuart.

 

[Ink stained Fingers]

what is the status, the computer can communicate with the printer, and there was no error condition so far. I don't think at this time that the problem is UPS related. If you get problems - e.g. problems with the ground connection, ground loops via USB and the mains, it might kill the USB port on the printer - or on the computer, but this is not the case. I would think at this time that there is a connection problem with the flat cable to the printhead - you may reseat this connector , but is just a guess, remote diagnostics is pretty difficult.
Are you running on 110V line voltage ? this may explain the 'feel' of 50V somewhere , on metal parts ? There is typically an EMI filter in the mains connection, in the power supply of the computer, and as well the printer , as a Y circuit, with capacitors symetrically to ground, and if there is no ground connection anywhere it works like a capacitive voltage divider of the line voltage with some low leakage current of 0.25mA or less. That's something you can feel nevertheless. Or do you have problems as well with other line voltage operated peripherals - scanner - another printer - monitor ? Are all parts of your system - computer, monitor, printer - connected to the UPS at the same time ? Do you know/can you check whether the ground connection within the UPS is connected through from input to output ? I have seen UPS units with a floating output like on a safety isolation transformer.

 

[Stuart21]

what is the status, the computer can communicate with the printer, and there was no error condition so far.

That's correct, does everything 'apparently' correctly - just no ink printed.

I don't think at this time that the problem is UPS related. If you get problems - e.g. problems with the ground connection, ground loops via USB and the mains, it might kill the USB port on the printer - or on the computer, but this is not the case. I would think at this time that there is a connection problem with the flat cable to the printhead - you may reseat this connector , but is just a guess, remote diagnostics is pretty difficult.

I have inspected all the cables & tested with a multimeter - all conducting - also I cut the last 1 - 1.5 mm from the most worn connectors so print head will be bearing on new flat cable conductor area.


Are you running on 110V line voltage ?

220V here - I have just swapped the power supply board for a new one - no change. The computer is on the UPS, the printer is direct on the mains supply. Reluctant to connect printer to UPS now as that is when the problems started, AFAI Can Remember. Also, I think I have seen recommendations not to connect printer through UPS. The USB ground should solve any computer to printer leakage -

this may explain the 'feel' of 50V somewhere , on metal parts ?

I am not feeling any residual voltage now -

but still stumped -

Thanks for your help ;-)


There is typically an EMI filter in the mains connection, in the power supply of the computer, and as well the printer , as a Y circuit, with capacitors symetrically to ground, and if there is no ground connection anywhere it works like a capacitive voltage divider of the line voltage with some low leakage current of 0.25mA or less. That's something you can feel nevertheless. Or do you have problems as well with other line voltage operated peripherals - scanner - another printer - monitor ? Are all parts of your system - computer, monitor, printer - connected to the UPS at the same time ? Do you know/can you check whether the ground connection within the UPS is connected through from input to output ? I have seen UPS units with a floating output like on a safety isolation transformer.

 

[Ink stained Fingers]

I don't think it's an UPS issue at this time but some signals are defunct to the printhead - cable/connector problem or a permanent defect e.g. the driver chip on the motherboard driving the signals via the flat cable to the printhead. But beyond that I wouldn't know how to continue at this time.
I can't think that a general statement - no printer on an UPS - is valid as such, you would need load/overload conditions and behaviour, voltage waveform details etc. It can probably be an issue with laser printers and the surge current from the heating/fusing unit on limited power units but that's not your problem at this time.

 

[Stuart21]

Thanks ISF. I have changed 4 print heads, 6 main boards, 2 power boards, & 3 main board to printhead cables, 3 computers (Acer, iMac, MacBookPro) 3 software downloads.

Still performing 'apparently' properly - but absolutely no ink printed on Nozzle Check, or general printing.

It is as if the whole system has been switched off, somehow?

I have a feeling its going to be embarrassingly simple - if and when we ever find a solution. ;-) ;-(

Stuart.

 

[Ink stained Fingers]

Wow, I wouldn't like to calculate the number of all possible combinations with these parts.
But now - one last question - which part/board/cable/assembly has not been changed yet in this exercise ?
And how many working printers did you take apart to get to the individual parts and assemblies ?