UM2 stopped printing

[KiwiMrDee 0]

I was printing last week. I tried printing yesterday and the start print progress bar sits at the initial position.
the print head moves but the bed and the extruder do not heat. (i left it for 30 minutes in case it was slow to heat, but there was no heating happening)
I can perform a material change - so the front panel->motherboard->hot end&stepper motor links are working

I can perform a manual extruder/bed heat up - they do heat and the thermometer is accurately reporting the heat up.
following tips elsewhere in this forum i have tried
* updating firmware and re slicing the designs 
* turning on/off for differing times 

* 'tapped' the mother board in the hope of releasing a stuck (unused) relay.
* tried printing via USB (FYI the head immediately moves as if printing but the heater does not kick in)

any other suggestions before I search for bad solder joints etc?

Edited August 15, 2018 by KiwiMrDee
more info

[gr5 2,094]

I'm thinking it's intermittent.  When you heated the bed manually you were lucky and power was working.  But when you went to print it was a different time and there was no power to the bed (K1 can get sticky -sometimes I give it a wack and it would start working or bad heater cables).  Anyway this is my first guess.

 

When it's just sitting there at the begining - go into the TUNE menu and see what temperature it is setting the bed to.  If the bed warms completely up only then should it start heating the nozzle.  If that heats up try exiting the TUNE menu and it should start printing.  Pay attention to the temperatures and report back.

 

It could be an intermittent cabling issue to the bed.  Usually the problem is where the wires meet the bed - either the cable needs to be screwed back down again or the terminal block on the bed needs its solder reflowed or the terminal block at the other end on the PCB needs to have the cables screwed down again.

[cloakfiend 995]

Thanks, good to know, as my UM2 is getting old now, will remember this should it happen to me one day.

[KiwiMrDee 0]

Thanks for the reply.
Start print. check temps via tune. both nozzle and bed reports room temp, no change.
stop print. set temp to 200 and bed to 60, both heat up and report progress.
start print. progress bar sits at initial position, nozzle and bed naturally cool.
I will check cable connections tonight and report back
 

[KiwiMrDee 0]

not sure if i would say intermittent. via tune ALWAYS heats up, via print NEVER prints up. has been consistent 3 days now.

Would you suggest I should try to set a jumper between NO and C on k1?
New UM2 board maybe?

[TMicke 23]

Not sure this helps, but this reminds me of my trials and errors.

I’ve only had my printer for a month and only used Simplify3D, but thought I would give Cura a try. It behaved just like you describe. When I pressed start print via USB the print head immediately started “printing”, without homing and raising bed. I tried a few times but it allways seemed to be the same. 

 

I have very little patience for this kind of things so I continued using S3D. Then yesterday I gave it another try, i was lurking around the settings and changed the G code flavour (is that what’s it called) to Marlin, in machine settings (not at my computer now but I think that’s where the setting is) don’t know if that was it but after that it worked, at least yesterday.

[KiwiMrDee 0]

Pulled the wee baby apart and found a very dry join on the heated bed.
Perplexed that I tried heating the bed by the front panel yesterday and thought it succeeded. I must have made a mistake.

thanks for your help.

BTW the merlin version supplied a very useful description of each stage of the process (heating bed etc) far more useful than a simple progress bar. any way the standard cura engine could have that as an option please?