If you hear a clicking sounds of relay inside that means your TV have a voltage on the power supply section.However,when the high voltage attempt to switch the voltage will dropping down and the TV won't turn ON that,s why you hear a HV (high voltage) charge or what we call HV (high voltage) oscillation..
That problem is commonly cause of faulty capacitors on the power supply section..You can easily identify the bad capacitors if it is look like bulged/dome or sometimes leak in oil but not all faulty capacitors have an obvious indication like that because sometimes faulty capacitors look like good but the actual capacitance value change its either lower or higher than the original capacitance value.In that case you a special tester called capacitance meter to identify the faulty capacitors..
This is the sample image of bulged/dome capacitors.
Please let me know if you found any bulged capacitors on the board..If that so kindly replace it only with same type,ratings and value..You can buy it locally or online and if you want sir I'll be the one search it online just give me the value ex.2200uf/50v. uf-means microfarad and v is for voltage..
If you can't find any bulged capacitors let me know,maybe that is time to proceed for advance troubleshooting.In that case you will need a multimeter tester for voltage checking..in this stage you need a moderate technical skills to perform this kind of troubleshooting this stage not advisable for the non-pro so let me know if you have any electronic background..If you don't have electronic background as much as possible I can't advice that because its too dangerous..I can diagnose the problem base on what you see and observation..
Just keep on touch!!!!
Hope it helps..
Try to watch this video on how to replace bad capacitors..