Just replaced both print heads (OEM) on my SG-300, now it won't print anything

[Dabistry]

Am I missing something? The ink is pumping through the lines just fine. It still just prints absolutely nothing. Please help!

 

[cornholio]

Are the flat cables connected correctly?

 

[damonCA21]

Check the fuses on the main board. It is easy to blow them when changing a head, and if you do then the heads won't print.

 

[MarkSnelling]

If the ribbon cables weren't put in the exact same order then you likely instantly fried the heads. Roland usually stands behind their heads but this might set off some tech's radar. Where did you buy the heads? I'd go back to them and see if they can get them covered under warranty.

 

[DL Signs]

Roland's are very temperamental with their electronics. One cable set wrong, one drop of ink on anything electronic (especially the ribbon cables and connectors, don't completely disconnect power and let capacitors discharge before you do anything, and fuses, sometimes even boards go bye-bye.

With new heads, have you run it through some powerful cleanings? is it pulling ink through the heads at all? If not it could be something as simple as the heads aren't filled, or cap tops aren't sealed preventing ink from being drawn through. If you're getting nothing at all, it's most likely electrical.

 

[Dabistry]

Roland's are very temperamental with their electronics. One cable set wrong, one drop of ink on anything electronic (especially the ribbon cables and connectors, don't completely disconnect power and let capacitors discharge before you do anything, and fuses, sometimes even boards go bye-bye.

With new heads, have you run it through some powerful cleanings? is it pulling ink through the heads at all? If not it could be something as simple as the heads aren't filled, or cap tops aren't sealed preventing ink from being drawn through. If you're getting nothing at all, it's most likely electrical.

I did not disconnect the power. I am clearly a moron. The tutorial I watched said nothing about that.

Yes, the ink is flowing fine, the dampers and lines have ink.

It sounds like I probably blew a fuse. Might be a dumb question, but where are they located?

 

[DL Signs]

Depends on what fuse, and where in the chain. There are a couple of std barrel fuses, but the ones that usually blow are soldered on the boards. You'll have to use a multimeter and test to see which one. It's been a hot minute since I dealt with Roland's, maybe someone else can point out the most probable one/ ones to check. I've had to replace them in the past, they're pretty readily available on line, inexpensive, and look like the ones in the pic. Always replace with the same value, these are what protect the boards from frying.

For any printer, if you're going to do any repairs where you even have to even touch wires, always fully disconnect power, and let it sit for a while for capacitors to discharge. Something as simple as inadvertently disrupting a ribbon cable by moving it out of the way to get to a screw or something else can cause a short, they're extremely sensitive. Always double/ triple check that ribbon cables are seated firmly and correctly before powering up again after doing any repairs. Ink is conductive too, so always make sure everything is clean before assembly and powering up.

 

[Zoogee World]

Like it's been mentioned, most likely the fuses on the mainboard. It's located at the back, in behind where the control panel is. Un screw all those screws on the back cover and it should be there. Make sure the power is off before you do any servicing back there. You'll need a multi-meter to test them to see if current passes through. If they are fine, it might mean you fried the head.

 

[Dabistry]

Ok, thank you all so much!

 

[cornholio]

The fuses for the printheads are on the carriage board on SG and VG printers. Not on the main, or head board, as they used to be on older printers with Epson heads.