LG 55UJ634 Series Service Manual page 92

`16Y OLED(C6) Power Board Diagnostic method
1
▶ Check power board voltage.
▶ Smart JIG: Fix the LCD MODEL switch to 24V.(Smart JIG)
3
▶ Connect the 24Pin Power Cable connector
to the Muitl Gender JIG 24Pin connector
2
▶ Disconnect the Main Board 24Pin Power Cable connector.
4
▶ When the OK LED(24V,12V) turns on, Power Board is normal.
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