Busted

[capitate]

Hi all, I feel I have a nightmare on my hands at the worst possible time.

My printer is Roland SC 540 EX

Recently I replaced a print head manifold on my Black print head. I replaced the part, and tried a test print of solid CMYK colors. The Black and the Cyan printed about .5" and then cut out (quickly faded out more precise). Mag and Yellow continued to print fine.

After that absolutely NO ink fires through those heads while printing. I can manually suck ink through to the pumps when they sit on the capping stations however. I also tested the pumps, and they are all working properly.

I switched the Mag & Yellow ribbons coming from the Carriage Board to the Print heads onto the Black & Cyan (and vice-versa). The Black & Cyan heads both WORKED, while the Mag and Yellow didn't as expected (albeit alignment was off of course).

I also tried new ribbons, and that didn't work.

So I've come to the conclusion that there is no signal getting through to the Black and Cyan to 'fire'. This leaves me to believe I have a problem with my Carriage board or possibly my Print Head Board.

Before moving forward to fix this, can anyone else think of OTHER possible scenarios or parts that could have caused this?

 

[Jack Knight1979]

You have a blown fuse on the head board caused by a bad head or ribbon cable short. This may have damaged the head board and will need to be replaced or repaired.

 

[capitate]

I used an ohm meter to test the fuses. I'm not sure how to understand this... when I connect the leads one way I get no reading (infinite), but when I switch the leads I get a reading that slowly builds. Also, the needle acts the same whether I set the meter to 10x or 1000x (it starts around 6 and then moves towards infinite)

I'm not really sure what to make of this. I tested the meter on a good fuse, and I get the correct reading of no resistance.

 

[Jack Knight1979]

partially blown? who knows.

I would check the data cables on the heads and make sure they're not grounding out. that's happened to me.

Have one of your heads started ghosting lately on the same channel you have a problem with now?

 

[otctech]

Are you removing the fuse when you check it? If not you could be reading other components on the machine.

 

[trillion]

check the transitor, it may be short.

 

[musquoni]

I had the same problem with my cj-540. Check the continuity between both sides of the fuse with the multimeter. That will let you know if the fuse is allowing current from one end of the fuse to the other. If not replace the fuse. The fuse on mine kept blowing so i checked all of the transistors and one was bad. I replaced it and all was good.

 

[capitate]

Just to update, it was the fuses. Once those were replaced it came back to life