Dead Power Supply Board in mi tv


 


Yes, I can definitely help you with tips to troubleshoot and possibly repair a Mi TV (Xiaomi TV) with no power / not turning on issues, especially related to the power supply. Here's a structured approach:

⚠️ Warning Before You Begin

  • Unplug the TV before opening it or testing components.

  • If you’re not experienced with electronics, especially high-voltage circuits (like TV power boards), seek professional help. TVs can carry lethal voltages even when unplugged.

✅ Common Causes of Mi TV No Power Issues

  1. Dead Power Supply Board

  2. Blown Capacitors

  3. Faulty Power Cord or Plug

  4. Main Board Issues

  5. Backlight or Inverter Problems (if TV turns on but no display)

🧰 Step-by-Step Troubleshooting Tips

1. Check the Power Source

  • Try another working power outlet.

  • Check the power cord for cuts or burns.

  • Test with a multimeter for continuity on the cable.

2. Perform a Soft Reset

  • Unplug the TV from the wall.

  • Hold the power button on the TV (not the remote) for 30 seconds.

  • Plug it back in and try to power on.

3. Open the Back Panel (If You're Comfortable)

  • Look for visual signs of damage on the power supply board:

    • Bulging or leaking capacitors

    • Burn marks or cracked components

  • Take photos of the boards to keep a reference.

4. Test the Power Supply Board

  • Use a multimeter to test DC output voltages.

    • Usually marked on the board (e.g., 12V, 5V, 3.3V lines).

  • If no output or wrong voltages → board is likely bad.

5. Check the Fuse

  • The power board has a fuse near the AC input.

  • Test with continuity mode on a multimeter.

  • If blown, replace with the exact same type. But remember:

    • A blown fuse often indicates another underlying fault.


6. Inspect and Replace Bad Capacitors

  • Common issue on Mi TVs.

  • Look for swollen tops or leaking electrolyte.

  • Replace with capacitors of the same rating (uF and voltage).

7. Replace the Power Supply Board

If bad components are beyond your skill to repair:

  • Look for a replacement power board online:

    • Use the model number on the board or your TV (e.g., L43M5-5ARU).

  • AliExpress, eBay, or local electronics parts shops may stock it.

🔍 Other Checks

  • Backlight Test: Shine a flashlight on the screen when powered on — if you see faint images, the backlight may have failed (not a power issue).

  • Remote Control Check: Try turning it on with the power button on the TV itself.

  • Main Board Problems: If the power board works but the TV is still dead, the main logic board may be faulty.

🔧 Tools You Might Need

  • Multimeter (digital or analog)

  • Soldering iron + solder

  • Screwdrivers

  • Replacement capacitors / fuses / power board

Want to Go Further?

If you can share your TV model number and/or a clear photo of the power board, I can give specific advice for components to check or replace.

Let me know how far you want to go with the repair!

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