Cómo reparar líneas rojas Y blancas en panel LG 4K NanoCell – Diagnóstico y reparación paso a paso

In this video, I demonstrate a complete diagnostic of an LG 50″ 4K NanoCell TV with a serious problem: upon power-up, a red vertical line appears, which then turns white, indicating a fault in the LCD panel. Throughout the video, you will learn: ✅ How to properly inspect the mainboard and verify its condition. ✅ Which voltages and signals to modify (or remove) to rule out electrical faults in some cases. ✅ How to inspect the COF chips for damage from moisture, burns, or corrosion. ✅ How to detect potential internal panel faults: open traces or short circuits in the GOA circuit. ✅ Why the problem sometimes lies in the ACF (TAP) ribbon cable—the connection between the COF and the panel—and how an ACF machine repair can restore the screen to normal. This tutorial is ideal for both professional technicians and hobbyists or beginners, and will save you time, parts, and incorrect diagnoses. Finally, I show the result: a completely restored screen. If you're interested in LG TV repair and want to save time and money, this video will be extremely helpful.