E0 Slot not working

So I finished the build on my MPCNC (all supplies purchased here), did some testing with a pen, experiencing some jitters, but still fine tuning the belts, so far so good.

Yesterday, I wanted to try my hand at printing a layer. Went through all the instructions, settings, etc.

When I tried to feed the filament into the preheated printhead, the extruder motor wouldn’t turn. so I shut everything down, and started troubleshooting.
Here’s what I’ve checked so far:
I’ve verified the driver is tuned correctly.
I’ve verified the jumpers are installed for E0.
I’ve verified it is preheating, and cold extrusion is not the issue.
I’ve swapped with the X axis driver, still nothing (no issues with X axis using the extruder driver during the swap).
I’ve swapped the E0 and X plugs, extruder runs on X, but X axis does not run on E0.
I’ve pulled and flipped the board, resoldered all connections to E0

Unfortunately, I have run out of ideas, and have not been able to get E0 working.
Any ideas or solutions will be greatly appreciated.


If you see nothing under close inspection of the pins, you can either swap the firmware to use E1 or send it in and I can test and fix it.

Thanks for the fast reply!
is there any disadvantage to using E1?
I’m assuming the multiple slots are for multiple tools setups?

I think for now I will try using E1 to get it going.

What all would you need me to send to you for repair?

Thanks again, big fan of all that you do!

Only disadvantage is no dual extruder. Chances are really good under the black pin sockets one of them is not soldered. Normally I would say a shield pin missed the connection to the mega but if you took it off to solder things I would guess you checked that. It also could be the mega but not usually. The biggest problem I have had recently with these is dry soldered lcd pins. So just assuming one pin didn;t get solder and is hidden by the black socket strip.

If you feel the need to return it PM me.

I should be fine with only one extruder for a LOONG time haha

I will double check the pins when I have a chance. Everything else seems to be performing perfectly.
I know you’re extremely busy, so if E1 works, I will likely just run with it, or purchase a replacement board, they’re not too expensive.

Thank you for all your help, and have a great day!

Just to cover the bases, you did verify the thermistor was giving a reading? The extruder won’t move until the hotend is reading high enough.

Yes, I did verify the thermistor was reading properly, good suggestion though!

What I ended up doing was ordering a replacement ramps board, which unfortunately also had the issue, so it seems the E0 slot on the mega itself is burned out.

I’m running off of the E1 for now, and haven’t had any issues since.

Thanks for the input!

I had the same problem but with the X axis, in my case it was a visibly damaged trace on the mega. Do you have a second arduino to check it?

> I’ve verified it is preheating, and cold extrusion is not the issue.
Maybe it is worth to re check it? Did you disabled Cold Extrusion check by M302 P1?