LG TV & Audio OLED65G3PUA 65" Class G3 4K OLED evo Gallery Edition Smart TV MAIN BOARD FAIL Error Fix: Main Board Failure

Error code MAIN BOARD FAIL on the LG TV & Audio OLED65G3PUA 65" Class G3 4K OLED evo Gallery Edition Smart TV means: Main Board Failure. Main board (motherboard) contains SoC, RAM, flash storage, and all input processing. Symptoms: TV won't turn on (3-blink LED), no video output, no smart features, stuck on logo, or complete unresponsiveness. Caused by power surges, capacitor aging, overheating, or firmware corruption. Replacement $100-300+.

The most successful fix is "Replace Main Board (Motherboard) Assembly" (hard difficulty, ~90 minutes). Estimated DIY cost: $200-$300. HomeMD has 2 community-ranked fixes for this error.

This error is rated critical severity. It is generally not urgent and can often be resolved with a simple DIY fix.

Yes — the top-ranked community fix ("Replace Main Board (Motherboard) Assembly") is rated hard difficulty and takes about 90 minutes. Tools needed: T20 Torx screwdriver, Phillips screwdriver, Anti-static wrist strap.

DIY cost: $200-$300. Professional repair typically costs $350-$500. Many homeowners save money by trying the top-ranked community fix first.

The LG TV & Audio OLED65G3PUA 65" Class G3 4K OLED evo Gallery Edition Smart TV has 8 other known error codes, including: ABNORMAL TEMP (OLED Panel Over-Temperature), APP CRASH (App Freezes or Crashes), AUDIO SYNC (Audio Out of Sync with Video), BANDING (Horizontal or Vertical Banding), BLINK 2X (Power Supply Overcurrent / Short), and 3 more.

Error code MAIN BOARD FAIL also appears on 6 other LG TV & Audio models: 55UQ7570PUJ 55" Class UQ75 Series 4K UHD Smart TV, 75NANO75UQA 75" Class NanoCell 75 Series 4K Smart TV, 86QNED80URA 86" Class QNED80 4K QNED MiniLED Smart TV, OLED55B3PUA 55" Class B3 4K OLED Smart TV, OLED65C3PUA 65" Class C3 4K OLED evo Smart TV, OLED65C4PUA 65" Class C4 4K OLED evo Smart TV. The fix may vary by model, so check each model's specific page for tailored repair steps.