Hi,
This kind of symptoms indicated of malfunction in the inverter circuitry inside the TV. It gone to overload due to the following reasons.
1. Busted bulb - If one of the bulb was already busted, the inverter gone to overload and the feedback circuitry will turn off the power supply to avoid further damaged. It can't be test by the multimeter but has a physical indication of fault like blackened end.
2. Faulty inverter circuitry - Once this circuitry gone bad same symptoms will be encountered. This was caused by shorted secondary high voltage transformer, driver transistor, open fusible resistor.
The unit must be take apart if not under warranty to check the bulb, and troubleshoot the inverter circuitry to determine where the fault came from.
If you don't have necessary tools and test instrument and can't
troubleshoot the unit yourself, I would advice you to look for a professional
to isolate the problem.
Also, check if your unit is still under warranty/extended warranty
period, avail it because the manufacturer will fix it for free. Opening the
back cover will void the warranty.
Hope I helped you.
Have a nice day!
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