I had the same issue. 31MU97B Monitor died when the UPS was turned off while it was powered on. All the voltages looked good. No parts looked bad. So I bought the eeprom replacement from:
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I had the same issue. 31MU97B Monitor died when the UPS was turned off while it was powered on. No lights would light up, nothing on the display. All the voltages looked good. No parts looked bad. So I bought the eeprom replacement from:
I had the same issue. 31MU97B Monitor died when the UPS was turned off while it was powered on. All the voltages looked good. No parts looked bad. So I bought the eeprom replacement from:
http://www.coppelltvrepair.com/p/1483/lg-31mu97-b-main-board-62882801-31mu97lm41c-eax66105904-eeprom-replacement-ic
Swapped this out and I'm up and running again. Your mileage may vary.
It seems strange that a read only eeprom chip would die, so I was very skeptical to start with, but this did fix it.