TOSHIBA LCD TV 50L2300U power-on flashing off the fault repair example - Appliances

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Electronic scale crystal oscillator 3.2*2.5mm 3225 16M (16.000MHZ) 12PF 10PPM 20PPM 30PPM

Inductance

SMD aluminum electrolytic capacitor

Today, I worked on a 50-inch "TOSHIBA" LED TV model: 50L2300U. The customer brought it in this morning, and upon powering it on, it flashed off after about one second. This kind of issue is quite common in LCD TVs, regardless of the size. Based on my experience, there are generally several possible causes for such a fault:

• Constant current board and power board – around 50% chance
• Light string and lamp beads – around 40% chance
• Mainboard – around 8% chance
• Other reasons – around 2% chance

This is my own analysis and not an official statement. To speed up the diagnosis, I focused first on the constant current and power boards, as they are more likely to cause such a short-term failure. After removing the back cover, I found that one of the HER3O3 diodes on the rectifier output had a reversed resistance close to forward resistance. I immediately replaced it with a new one of the same model, and the TV worked perfectly after testing. The repair cost was $228.

It's always satisfying to fix something that seems broken at first glance. Sometimes, a small component like a diode can be the root of a major problem. I believe that careful inspection and a methodical approach are key to efficient repairs. This case was a good reminder of that. If you're facing similar issues, don't hesitate to check the power supply and constant current board first. Good luck with your repairs!