Replaced power Supply Board LC391EM3 LCD TV. It still won't power up.

the whistle is the crowbar action in the power supply as it detects an error it slams that current into a coil an shuts.
try isolating the power supply pull all connectors
if nothing happens no whistle then either its external board or one of them gives it feed back to allow it to turn on . best can do.

The fuse is located on the switched mode power supply board.

The fuse is located on switched mode power supply board. If the fuse has blown the set will be dead no standby led light on front of set also when you plug the set into a power outlet you should hear the relays clicking. if you don't hear the clicking then the fuse has blown or another part of the power supply has failed and will require service.

No this is from the power supply board having bad capacitors on it. You can replace the whole board or you can do component level trouble shooting.

Sounds like the back-light inverter board has damaged. Check it.

Hello,

Your power supply board is dead, u know basic electronics' and soldering? Most of the times, the power supply board just have dead leakages gases capacitors.These capacitors always bulges up on it top,or puff up on it top.Replaced these gases leakages capacitors will get your TV power stable,and work again.Or tries websites like Shopjimmy.com,Ebay.com to buy a whole refurbish power supply board for the replacement.

I hope this will helpout ......

90% to 95% ur tv have a dead power supply board only.5% ur tv could have both dead boards the tv power supply board and the main tv Tuner signal board too.The tv power supply board.That the board,where the power a/c cord plug into it.The tv main Tuner signal board,that the board where all the exstented devices and the tv incomming broadcasting signal cable wire plug into it.Tries websites like Shopjimmy.com,Ebay.com to buy a whole refurbish power supply board for the replacement first.The tv problems should be fixed.If not than the main tv Tuner signal board is dead too.Must be replaced also.

Yes,very fixables.Ur tv power suppply board have these parts call capacitors.They are dead and gases leakages,not total,but dying.These capacitors they alway bulges up on it top,puff up on it top,these capacitors are dying,that why tv still have power but it take up to ten min. clicking to recieve power to the rest of the tv.The power supply board,that the board where the power a/c cord plug into it.U have basic understanding of electronic's?U have tools,soldering iron,desoldering pump,solders?Take the tv aparts.U just looking,searches all around the power supply board and replaced these dead,dying capacitors that are bulges,puff up on it tops.Replaced these gases leakages capacitors,ur tv will have it power back to normal and work on the first click.Or tries websites like Shopjimmy.com,Ebay.com to buy a whole refurbish power supply board for the replacement.

Hi,
Its fixable problem like power supply board replacement will solve the problem.
Unplug tv from wall socket for couple of minutes, replug back in and turn it On.
If problem still exist then most likely power supply got fired and will be replaced, local tv repair shop will help you to replace power supply board.
Thanks.