LG OK75 - Electrical Troubleshooting Guide: LED;VFD Issues

No LED
Is Vcc (DVCC_5V)
supplied to IC206, IC209?
Check or replace IC203 block.
YES
YES
NO
Is SPLED & XFLED_5V is normal?
Check or replace IC206, IC209.
YES
NO
Check or replace LED harness cable.
No VFD
YES
VFD_12V is normal?
VFD_3.3V is normal?
VFD_CLK, STB, DO is normal?
Check or replace Q202, Q205.
Check or replace Q203, Q206.
Check or replace R808, R811, R814.
YES
YES
YES
NO
NO
NO
Check or replace VFD.
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ELECTRICAL TROUBLESHOOTING GUIDE