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I was fiddling with my layer fan connection just now and shorted something out. I have read some threads where people used some automotive fuses as quick fixes while they waited for the real deal to arrive. Problem is, I know barely anything about wiring at all and I am honestly surprised I was able to assemble this printer.

I have a multimeter, a soldering iron and I can get fuses but where do I need to look at first on this machine in order to narrow it down?

Machine still turns on and I can hear the fans humming but I have no display, so I guess that's a decent starting point - Rostock Max V2 machine by the way.


Any help at all is greatly appreciated, thanks.

Look up the Rambo board on the RepRapWiki to see where the fuses are on your particular version of the board. Mine are near where the thermistors plug in.

You can check what's good and what's bad with a continuity tester (sounds like you already know that), and then solder leads to the end-caps of the blown fuse that go to the automotive fuse-holder.

Hack at your own risk, obviously. Hope you are printing again soon!

You have blown the fuse in the F3 position on the RAMBO board. This is the fuse that controls logic for the board, No working fuse means no working working RAMBO.

Here is a diagram of the board layout and fuses: http://reprap.org/mediawiki/images/b/b4 ... -fuses.jpg" onclick="window.open(this.href);return false;

Here is where you can source replacement fuses:https://ultimachine.com/content/fuse-0448005mr

Just a friendly reminder - never work on the electronics with anything powered on. If the RAMBo was powered off and you simply swapped the + and - wires on the fan it would have either run the fan in reverse or not at all but it would not have caused a problem with the RAMBo. It appears as though you shorted something working on a hot board. We've all done it! I've personally sent 3 RAMBos back to Ultibots for repair after swapping thermistors and blowing the thermistor ports. Now I always power down!