not printing cyan or black Roland SP300v

[Mikecolle]

yes we went with the same rating and wattage but with glass fuses to tell if they are blown, im a drafting and design person so i have a replacement board being prototyped since this thing seems fairly common on this model of printer

 

[Mikecolle]

im convinced its a page file, have verified the head works on another sp300I but its not firing on my sp300V. anyone have a sp300v and want to drop the page file binaries

 

[netsol]

the way to troubleshoot this problem, IF YOU HAVE COMPARED D.C. VOLTAGES on the power transistors, is with an oscilloscope. You can see if a signal waveform is reaching each transistor pair, and actually reaching the correct terminals on the printhead. You can compare a functioning output transistor pair to a nonfunctioning pair.. you can check inputs and outputs on the head carriage board and determine where you stop passing a signal waveform when you attempt to print

I am assuming that your dampers are full of ink, and that sort of thng. (We are both working with the assumption this is an electronic problem)

Do you have a service manual? I could loan you a scope for a few days, if it helps

 

[netsol]

It's interesting. You have obviously had enough trouble in that circuit to replace the fuses with socket mounted.
How many times has a fuse blown? (4 years ago I replaced my b channel fuse [yellow/black] with a circuit breaker to simplify troubleshooting). It's a sc545-ex, same vintage, very similar circuit

 

[Mikecolle]

i replaced it once, had the issue of a short when we moved the machine to our last location. and if the transistor was the issue it woulnt fire the other head when the cables are swapped. on the carriage, im going to try ordering new cap tops and see if that works, but they are both full of ink currently. as stated before i can manually pull in through the head, but it wont print on the head. i have one more print head i will be trying, in the mean time. shame there isnt a way to just test the head without putting it in and out of the machine

 

[Mikecolle]

never did figure it out, if anyone knows someone near lebanon oregon that could help it would be greatly appreciated

 

[Mikecolle]

so i have tried every solution from changing parts to replacing heads, i think this is it for my printer

 

[netsol]

Mikecolle
You need someone to troubleshoot the electronics

Once again if you have someone capable of some electronic troublreshooting, i can loan you an oscilloscope if necessary and can "Kibitz"

 

[AmberM]

so i have tried every solution from changing parts to replacing heads, i think this is it for my printer

Did you ever find a solution? I’m going through the exact same situation! I have tried 4 heads now. Changed everything, checked fuses, etc etc. My husband is a master electrician and electronics technician who routinely works on more complicated things and he’s frustrated.

The oddest thing is that the old head that had drop outs so I was replacing it - does work when I put it back in! Yes, head ranks changed each time. It’s head 1 (black/cyan) and an SP300v.

Curious if you figured it out.

 

[damonCA21]

Did you ever find a solution? I’m going through the exact same situation! I have tried 4 heads now. Changed everything, checked fuses, etc etc. My husband is a master electrician and electronics technician who routinely works on more complicated things and he’s frustrated.

The oddest thing is that the old head that had drop outs so I was replacing it - does work when I put it back in! Yes, head ranks changed each time. It’s head 1 (black/cyan) and an SP300v.

Curious if you figured it out.

There are a few common things to check. Assuming your dampers are fine, and when you do a powerful clean then you are getting black ink coming through? If so you know the head isn't clogged. The old head may print because it still has some ink in it, you need to ascertain if the new head is actually getting ink into it, so doing the power clean will confirm this

If the old head is working when you refit it then it could be a cable problem and changing the head moved the cable enough to make a good connection again. It could be a fault with the print carriage board ( the one that the head cables connect to )

Also try new cables again. I have fitted brand new cables before and had them not work!
Head rank wouldnt stop it working, so that isn't critical.

I would then put the new head back in and try a cable swap from the yellow/magenta head. Plug in the cables that should go it into the black/cyan head, and the cables from the black/cyan head into the yellow/magenta one. Make sure you turn off the printer and unplug the power lead, then leave 15 mins to be completely dead before doing this otherwise you can cause more problems !

Do a test print, and if the black head fires, then you know the head is working ok and getting ink. The printer now thinks it is the yellow head, so is sending the yellow/magenta signal to it.
If the yellow head fires as well then you know that the signal that controls the black head normally is getting from the main board to the head ok.

Really you need to test the signal path for the head. It goes from the main board via the main printer ribbon cables to the printer carriage board, then from there to the head itself. Doing the cable swap will let you know for certain if the black head is working, and if a black/cyan print command is being sent from the mainboard

Try these first and let me know how you get on