Nozzle and build plate randomly won't heat up on Ultimaker 2.

[UltimakerPro 0]

Hey guys! So as the title says, my print head and build plate just stopped heating up randomly. I can manually get them to heat up when I go through the Maintenance menu but when I set the print from the SD card, the progress bar doesn't move and nothing heats up.

I tried formatting the SD card and I also tried an SD card from my other Ultimaker 2 but it just doesn't work on this Ultimaker.

I checked all the wires from underneath and they seem to be plugged in (although I could have perhaps missed something).

I bought this Ultimaker about 2 weeks ago and its worked perfectly up until this morning when I turned it on.

Thanks!

[gr5 2,172]

It's probably the relay known as K1. Watch this video:

Once K1 closes it will stay closed until you cut power. If you let it cool a few hours and turn it on it will work fine. Watch the video! It's only 1 minute.

I fixed this by shorting out the 24V that K1 controls. I spoke to Siert (one of the founders) and he said that's a good solution and that K1 isn't used for anything - it was intended to be used as a safety power cutoff to be connected to external power off switch or signal but it's never been implemented.

If you aren't into hacking K1, first prove that you have the same problem by following the things in my video and checking the lights and tapping the relay. Then post back here and then ask for a new PCB from whomever sold you the printer and refer them to this thread.

While waiting for you new PCB you can use the trick in my video for now.

[UltimakerPro 0]

Thanks gr5! I watched the video and tried your suggestion but I don't think its the K1 relay. When I set the UM2 to print, the red light for the build plate turns on while the nozzle light remains off. I tried tapping the PCB but it didn't change anything.

Also, I have no idea why but the build plate now heats up when I set it to print! I'll test to see if that stays consistent. All that's left is to get the nozzle to heat up as well!

Any other ideas though?

[Labern 774]

The nozzle only starts to heat up after the build plate has reached full temp.

Have you waited long enough for this to happen?