Emerson TV not working

Check capacitor on power board they must be changed 1st

The power supply regulator board to your TV is now working fine, and has no problems at all, as, there is standby light. Check all the other voltages comes out from the power board, to main board. If all of it found OK, the fault should be at its main board.
About blinking of standby/power light;
These blinks (flashes) are fault indication. By the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit stage inside the TV. Count the blinks occur at one time switch ON, carefully. Do it once again, and make sure about the number of blinks. If the flashes are continious, non-stop, the main system control IC should be suspected. If you wish to get more details, check the site linked here. It has blinking codes detail to many brand TVs. Pull up older posts. Check the site in 'Mosaic' view. It will make search easy. http://electronicshelponline.blogspot.com/

Continuous blinks of standby light indicates a fault in the IIC data bus. The main board is likely to be faulty. If you wish to know more Check this link.

It sounds that the main digital board has damaged. 12 blinks indicates it. if you wish to know more check this link for more details about 12 blinks to Emerson TVs

Look at this link on the bottom to see what the blinks tell you.

http://www.agoraquest.com/viewtopic.php?forum=70&topic=31721

Mike

Mine stayed in stanby mode and all I had to do was to switch the plug to a different outlet. The power strip it was on wasn't providing enough power. It worked fine for a month before I had a problem.

It does sound like a power supply problem but that can be misleading because a problem somewhere else in the TV can be "holding down" the power supply. This can usually be determined by using some isolation techniques.