No need to answer. You removed the back and so you are. Let's carry on.
With the power removed and you being very aware of the lethal voltages and more (this is all the warning I'll give) I would see if there is a board that holds the power button and then look at it closely to see if I could unplug and plug it back in. If that doesn't help I see where the cable goes to and I unplug and plug it back in.
If that fails to help I continue to unplug and plug in all cables and boards I can do easily. I've lost count how many times this brings a set back to operation.
Beyond that and you'll need a service manual and the usual shop gear.
Bob
Hello, I have a 32ld400 LG LCD tv that is 3 years old but has been taken care of. When I try to turn the TV on by the TV itself and the remote ( remote has fresh batteries and nothing is blocking it) the tv does not go on, however the red light stays on it should turn green but it just stays solid red. I took the back of the TV off to see if maybe the Capacitors had gone bad but they are still flat and nothing is oozing out of them..I really didn't see anything that looked damaged..not sign of anything being burnt. Can someone please help me figure out what may be causing this? Is it the power supply/board? I don't have a tool to test the volts so I am not sure. Thanks.

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