The TV is on protection.
Protection is a special diagnostic mode that will keep the TV in standby as an internal fault had been detected.
The clicking noise is the protection switch that keeps turning the TV off to prevent further damage.
The fact that TV restarts after unplugging lets think to a fault on power supply board inside TV.
When you unplug TV you discharge PSU capacitors, and that is the reason why the TV restarts afterward
First test the unit on a different socket. If you are using a surge protector, remove it.
Try also leaving the TV unplugged for a longer time, let say several hours.
Also unplug all connected device, and leave only the aerial cable, a defective receiver box or DVD can cause the same problem.
If that does not solve the problem, then the TV is faulty, probably a defective PSU (power supply) board. The part must be tested before replacement.
In this case, locate any good qualified repairer.
If you want to DIY you find parts here. You will find schematics and diagram to test the TV on the service and repair manual that can also be purchased from the seller below.
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