Hi @fpnguyen ,
From the 1st image, R405 has gotten hot and may be damaged - black spot on left side?
My eyes aren’t the best so I can’t quite make out the colours to know its’ value. Here’s a link to a 5 band resistor colour code calculator which should help to find out the value if it is open circuit.
R404 is the same value resistor as far as I can tell so if it measures OK to what you think it should be as per the calculator then if R405 is faulty you’ll know what to replace it with.
If the resistor is faulty:
Replacements are from places such as this or even Ebay once you know the value of the resistor.
From its’ size it looks like it has a 0.5W power rating for if and when you go to find a replacement. Resistor power ratings are as follows : 0.25W, 0.5W, 1W, 2W, 5W, 10W etc
Be aware though that there is always a reason why a resistor overheats and usually resistor failure itself is not the first reason. It is what the resistor is connected to that has failed and has caused excess current to flow through the resistor and damaged it.
It looks as though the resistor may be associated with QW401 (under the heatsink) but you would have to trace the tracks that the resistor is connected to to find out and if it is test it to see if it is OK or not.
If the resistor is not faulty:
I can’t tell if the power transformer in the middle of the board also got hot and is faulty or if it is just the way it looks in the image.
Without a schematic of the power board (search online for “(insert the powerboard “board number”) schematic”, in the search term) it will be very difficult to find the problem(s) as you would have to initially do point to point testing of the components paths and components using an Ohmmeter, drawing the circuit as you go and then work on a “live” board with a Voltmeter looking for the problem.
Fault repair at board level without a schematic, unless you are familiar with the particular circuit, is very time consuming and very difficult.
It may be easier to try and find a replacement power board, again by using the board number.
How old is the TV? If less than 12 months it should be covered by the manufacturer’s warranty so if it is go down that path first.
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