Well given the fact that that particular fuse needs to be between the board and the extruder, I used the cable which sits right between board and extruder. I used a car fuse holder which I attached to the metal chassis and it's working great

I just mounted the whole thing and it works. All that remains to be done is to find a 12V 3.5/4 A fuse to put in there

Cars use 12 V batteries. I imagine with a car fuse holder I'll find a fuse for 3.5/4 amps. Other people seem to have gone this road and it seems it worked ok for them. I'm just copying

PS Also one thing I am certain: I'll never brush my extruder with it being on from now on. It's so nice to see the old lady working again

That sounds great. I think many people have this issue, and there are guides here and there but often missing some details, it will be great if you can post a comprehensive "HOW-TO" guide with links to other guides, the choice of fuse (where to buy), stl file for fuse holder/mount etc.

I just mounted the whole thing and it works. All that remains to be done is to find a 12V 3.5/4 A fuse to put in there

Cars use 12 V batteries. I imagine with a car fuse holder I'll find a fuse for 3.5/4 amps. Other people seem to have gone this road and it seems it worked ok for them. I'm just copying

PS Also one thing I am certain: I'll never brush my extruder with it being on from now on. It's so nice to see the old lady working again

Also tape your wire to the board after finish so that is don't wondering around.

So, first, I must have misremembered the succession of events. While the heater was on, I must have scraped it with my metal brush thingy and that in turn must have shorted the 12V output to the extruder, which in short broke the R271/J4 0 Ohm rezistor which I understand is used as a 4 Amp fuse. I measured it and it says resistance 1, which basically doesn't allow electricity to passthrough.

So I decided to solder it out, short the two pins together and install a detachable 4 amp fuse on the wire itself. I'm not very good with soldering so I don't want to solder too much on the board. but as I understand it it's perfectly ok to use a fuse on the left pin wire.

What do you think?

As I was fearing it's not the cable. I checked connectivity of the cable and that works fine. I checked the heater with a battery for a few seconds and it got a bit hot.

Also I checked with a voltmeter thingie the Voltage out of the white connector in the middle of the picture with 2 white wires which feeds the heater in the extruder. First I turned on the printer, then, turned the extruder on to 160, and checked the voltage, it was steady at 0.

Also, the second picture shows a screenshot from the webpage of repetier server. A cycle consisting in turning on printer, turning on the heater, error and shutdown. I seem to remember that repetier server used to draw with green stripes the moments when the board would send electricity to the heater. But according to this graph, the board itself is aware that is not sending electricity.

https://plus.google.com/photos/11445465 … 2143591618

I've found this screenshot of someone else showing how the graph is supposed to look. Those green bursts of energy showing output.

I have seen the board itself has a second pair of everything for another extruder. If there's no other choice I guess I'll try to convert to use that before trying a whole new board completely. I'm open to suggestions. This is not a good day for me

Like the subject says I have a Da vinci 1.0 model 1 (with JP37). I first modded it with luc's repetier variant of the firmware. To give a time scale that must have been like 3-4 years ago. Everything went great. Upgraded since then a few times. I'm up to date on that.

Next, 2 years ago I modded it with a custom extruder, e3dv6. That upgrade went ok as well. A kink here or there. Especially with the thermistor. All things considered this is not the problem i am having now. If the thermistor would have been at fault, my printer would have shown 5 degrees on extruder and that's a pretty good indication the thermal sensor is not connected.

No. The problem I am having now is with heating up the extruder. I didn't bother the cables. But all of a sudden (and it was sudden)  after a successful print was finished, went to the machine, took out the old print, the temps on both extruder and bed were going down, and tried from the menu of the printer to turn back on the extruder. the machine took the command like normal and while I was examining the print, i was expecting the extruder temp to go back up. but it wasn't. it was going down. The previous printing temperature was around 240. I caught it back down to about 215. and with my left eye it was 210. 205 (WTF) and I think around 200 the printer went in error mode extruder/sensor error.

I'm pretty sure I didn't hurt the cables when I took the print out. The connections I made 2 years ago with the new extruder I think are pretty safe. If it's not the cables... or the hotend (which I can replace)... I really dont know what is.

So please help me. Tomorrow will be a dark day. I really don't like when my printer is not working. And I'm further upset by the idea that I can't fix it. If it's not the cables, or the hotend... what else could it be? If it's board related, could I hope to diagnose it or repair it? could I change the board with a ramps board? Throw any ideas at me... I'll google everything.

PS no, I didn't test the cables. I'm upset. I had a few beers. I'll do it tomorrow first thing. I'll use my saturday for this. I already let it cool off a few hours. looked with my eyes at the cables. I really dont want to use the little voltmeter joke of a tool to see if the cables give 12 volts. I already know that rebooting it doesn't help. I'll try tomorrow to see if the board gives 12 volts and if it does is easy. either the cables or the hotend needs replacement. but what if it's the board. that's just scary for me