Dear EEVblog forum,
I am really desperate

I designed, build prototypes of a new product for my colleagues. It is rather simple, Arduino Nano (will probably be replaced for just Mega328 in the future), 4x20 LCD, linear voltage regulators, some relays, OPAMPs and bunch of passives. It has a pack of 8x2,2mF capacitors. And it is powered with 12V/1A DC power supply -
MEAN WELL GS12E12-P1I.
Now it is being tested for EMC.
I was not present for the test but it failed to survive the 2kV pulses injection to the 230V AC. (we will sell it as a complete unit with the power supply so we were told it needs to be tested with the power supply)
My colleague (not an electrical engineer) was there and the only info I have is - it was dead and it was not able to recover by itself -
unplugging of power supply was necessary.
I added the watchdog (I know it should be there from the beginning) and added a massive ferite of shame to the 12V power cable.
Again I was not present but it failed again - this time at least I have a video of that. It indicates that Arduino is working but the LCD is dead and the rest is almost dead -
the circuitry (mainly relays) which is powered directly with 12V is not working.
Now I have two questions:
Is it possible for the hd44780 LCD to freeze without self recovery with such pulses?Is it possible that MEAN WELL GS12E12-P1I power supply enters some kind of half dead state in which it does not provide 12V but maybe only 5V (5V-1,2V drop = 3,8V... enough for Arduino to be alive, probably not enough for the LCD, not enough for 12V relays)? I mean it already has all the certifications. Or is it some kind of undocumented safety feature?
From what I saw it looks the power supply is the problem.
Next time I will try different power supply and will measure voltage after the test but I need to be prepared.