Epson L365 burned transistors

[Alexander Popescu]

The heads were clogged and were not printing red at all even though i had more than half a tank of ink.

I have cleaned the head, first with isopropilic alcohol (didn.t do much) then with water and cleaned till water spewed clean out the nozzles. Put the head back. Printer turned on. Did it.s thing (head alignment back to docking position i guess). Turned itself off. Pressed the power button. Power led blinked once and nothing. dead.

Dissasemled the damn thing. Realised (seeing videos on yt) that the main transistors were burned. C6144 snd A2222 are the culprits. Bought new ones. Put them back. Pressed the power button. Led blinked once. Dead.


So. I assume that something is burning the transistors. (Maybe they are receiveng more voltage than they can take i guess !?).

What do you guys think?

Thanks.
Alex

 

[Ink stained Fingers]

You apparently took the printhead out for cleaning; there could be a risk of moisture at the flat cable connector causing a short and killing the circuitry or the flat cable is misplaced at reassembly.

 

[Alexander Popescu]

Yes. I took the printhead out for cleaning. But: i let it dry for 24 hours in a warm place. Nevertheless, i could have misplaced the flat ribbon cable when mounting it back. But first time when i've pressed the power button, the printer did start and did some printer related noises. The head went sideways and docked itself in its position. Could it be that i i poorly mounted the ribbon back?

 

[Ink stained Fingers]

Epson maintenance manuals typically don't offer any details how to do component level repair of controller boards, I don't really know how to go from here.

 

[Aparsons]

Have a similar problem with an Epson XP 335. Cleaned the head with cleaning fluid and a syringe (carefully). A great glob of black (it was the black that was blocked) came up on the suction and then eased some cleaning fluid through the head. When went to do a nozzle check it went off and has not worked again. A disassembly showed that the two power transistors had failed short circuit which sorted the power supply which mercifully shut down.

I note that there are a lot of these A2222/C6144 power transistors on ebay - but has anyone effected a successful repair or do they just go pop again?

If it is the head shorting out the power transistors then ssurely nothing but a new head will fix it.

On reflection what do these power transistors drive? The head does surely not need that much power? Will investigate further but any experience or information would be useful. This seems a common problem but nobody that I can find has logged a successful solution. They have either hit it with an axe or mended it and are living a happy life - but which is it?

 

[Azelus]

If printhead burned after manual cleaning, then you must replace printhead (FA04000), transistors and, highly likely, integrated circuit E09A92GA. In very rare cases some resistors burned too and connectors of FFC are damaged.
Simple description of printing technology can be found in old service manuals (for example, Epson C60). More serious description can be found in patent US8240798.

 

[Aparsons]

One of the YouTube videos on replacing the Printhead said that there are voltages of 40-50 volts on the Printhead which might explain why it reacts so badly to a bit of loose cleaning fluid.
Haven't been out to my workshop as it is too cold at the moment but will remove the Printhead for examination to see if there is any visual damage. There is absolutely no sign of damage to the power transistors so it must have been a swift death rather than an overheating.
Have been out to my workshop and have removed the power transistors and then carefully cleaned the holes with desoldering braid. Have taken the head out and there are no signs of any frying or anything untoward. Have given this a good clean and rinse and then dried it with paper towel, Have tried to flush as much ink out of it as possible just by rinsing under the tap so that when I dry it by the boiler in the kitchen I'm not creating a seriously dried ink clog problem.
With the power transistors and the head removed the printer powers up. Nothing moves but the panel comes on and stays on with a CX-01 error message. No surprise there, half of its parts are missing. However it does mean that the short has been removed and we may be able to go forward. Have ordered 5 pairs of A2222/C6144 power transistors from the People's Republic and will await their arrival. When I first removed the transistors the printer behaved as before. It took a couple of goes of desoldering the holes and reseating the cables before it came on. I'm going to have to be careful and meticulous when I fit the new transistors as there is not much space between the tracks.

Has anyone successfully repaired one of these printers by replacing the power transistors? There are certainly plenty of these pairs (A2222/C6144) for sale so one imagines they cannot all be in vain?

 

[Aparsons]

Have installed the transistors and the panel comes on and the carriage twitches but does not move. The error is 0xF1. The transistors are good but cannot give it anymore time or effort.