UM2 replacement main board problem.

[naz72 0]

I had a problem with my main board and you sent me a replacement 2 month ago, I never tried replacing it since my Extruders are blocked & I am still waiting for a replacement.

Anyway I decided to fix the new board & I connected all the wires right, I am sure of that but once I power on I only see the small green led light on the MB lights on & I hear the stepper motors arm, but the LCD screen doesn't turn on, nor the light inside the UM2.

When I tried switching the two LCD cables around the & turn on the power, the lED lights in the UM2 turns on but still the LCD doesn't work nor can I do anything.

I did connect the UM2 via USB cable & flashed to latest firmeware but still no luck after I power cycle.

Any idea what's the problem or what else I can do ??

[naz72 0]

One more thing I forgot to add:

I also tried disconnecting all the cables from my extruder and also the heated bed incase that was causing a short circuit but still no luck.

[jonnybischof 60]

Why did you have to replace the mainboard?

Was there some electrical surge, or a lightning strike? Because if your first mainboard was destroyed, it may have taken the LCD expansion board with it...

You can't do much wrong with the UM2 EXP connectors: it's impossible to connect them wrong (reverse polarity), and confusing EXP1 with EXP2 "should" only make it not work, but not damage anything.

Of course there's always the possibility that your flat ribbon cables are broken. If you have a multimeter, try checking the cables for bad connections.

Or you can just take a close look at them and see if everything seems ok.

Chances for bad cables are usually pretty low, especially if the wires are never moved around or excessively bent.

 

[illuminarti 18]

Probably a good idea to take a photo of the electronics board, and post it here. Get some fresh eyes on it, in case there is something you've missed. After you've looked at things for a while it can be hard to spot problems.

Did you also check that the connections are all good at the screen end?

And did you check that when you updated the firmware, you put the UM2 firmware on it? (I.e., make sure that Cura was set up for an Ultimaker 2 when you did the upload)?