42" 1080p Flat-Panel LCD HDTV: no signal after power outage and have tried resett...

Check the outside antenna ,if you have one for direction it may have swung round,or the set could have Copt a surge,fit a surge board to mains power.

Now tv turn on have power LED and OPC LED lights indications flashes together?Yes,this problems,it is the tv Tuner signal board it is causes and the problems.That the board where the incomming broadcasting signal cable plug into it.If turn tv on.No power LED light or any kind LED lights at all.Yes.Than the tv power supply board that the cause and the problems,that the board where the tv power a/c cord plug into it.U have some basic mechanicals skills like take things aparts and putting it back together again?Yes,tries websites like Shopjimmy.com,Ebay.com to buy a whole refurbish tv Tuner signal board or tv power supply board for the replacement.

Leave it unpluged for 40MIn. for the TV processor, to reset back to normal. If that does not work then replace power supply.

check the power supply board , you need to change or repair it

Is it grainy on all inputs? DVD, TV, some other source?

Tries unplug,replug an hour later,let the tv reset itself back to factory setting.After,turn on the tv,go to the menu,go to sound on ur menu go down to reset the sound.The functions should go back to normal,not than.Ur tv Tuner signal board have a short,in the power outage occurance.

Try unpluging it for 30 seconds and plug it back in. This is how some electronics are reset.

Try using a different outlet, the outlet or the tv may have been damaged in the surge. In the case of the tv contact the manufacturer and see if it's still under warranty. There may also be a way to 'reset' the tv by holding the power button down, try looking in the manual or calling customer support. In the future use a surge protector, many of today's electronics are still sensitive to power surges, older tv's were more resilliant than today's in this regard.

Make sure you get colors by bringing the TV menu and see if looks normal, if it does
maybe the problem us the signal source

Look at the Power Supply board of your tv to see any puffed capacitors. If you notice some of them failed, just replace them.