Tv came on after changing main board,but when I unplugged it to move it to a cable line in another room the tv would not boot up. The light is just blinking green as it did before changing the main bo

try a different input then call a local repair service

We need to replace the mother board and the led panels of the led tv

You should NEVER remove the ribbon cables while the TV is on. Try unplugging the cables again with the TV off, and while the cables or off power on the TV. Power off again and connect cables. If that doesn't work you may have to change the screen.

You may have a back lights problem.

To test the back lights, you need to disconnect the cable between the main power supply & the main board, apply the AC power to the power supply, if the back lights are not light up, or blinks, the back light are defective.

The mother board is faulty. You have to change the main board. If you wiah to get some details about flat panel TV repair then check the below link.
http://electro-medical.blogspot.com/

nplug the switch board from the main board. If it does the same thing, change the main board. If not, change the control switch board. Also try it back where it was before to see if it keeps doing it. Good luck,


Serge.

ok I have ran across this before.. First turn on the TV and go to a channel u know is good, with sound.. now turn off lights in the room.. or just darken the room.. next take a FLASHLIGHT and turn it on and shine it into the front of TV . If u see the images on the screen when moving the flashlight around. that is a good sign.. That usually means the Backlight board or boards are not working..with the TV on and in a darken room you should be able to see light coming through some of the Vent holes in the back cover, that means the Backlight board is working. from what u say I would bet on the backlight boards. pretty easy fix.. Unplug from the AC outlet. remove the back. Now be careful back there cause u can still get Zapped. I ALWAYS take pictures of the back (close up of the model and serial #'s) I take several pictures of the inside of the TV. some TV's have the Backlight board or boards on the side of the screen and some have the backlight inverter built in the main board, since u have already replace the main board u must have backlights separated. . Take close up shots of the board, and write down all the #'s from the board and when u order make sure u order the exact one..I never remove the bad board till I have the new one ready to install. I always go to ShopJimmy.com first to see if they have the part. Then I check Amazon, and then eBay. in that order.try to buy NEW boards if u can.. Hope this helps.

TV may be on the wrong input and that will give you a blue screen. When you turn the TV on and the screen starts lighting up it should show on the screen what input the tv is on. If it is not on correct input change input with the TV remote or buttons on the tv. If it is on the correct input try a power cycle on the cable box, just unplug the cable box power cord for a few seconds and then plug it back in. If neither of these solve the problem describe how the cable box is connected to the tv.

Most likely you have a fault in the back light circuit. To verify this, turn on the set, when the screen goes black, take a bright flashlight and shine it on the screen. It may be easier to dim the lights in the room so that you can see the faint image on the screen. If you see the faint image, you indeed have a back light problem. You will need to get a diagnoses performed on the set to track down the problem

The problem is the main board in your TV. If your TV is a LG or SONY brand, please try this:

Re-Flow Soldering Procedure for LG Main Board

1.Pre-heat your kitchen oven to 385 degree (No more than 400 degree);

2.Put the main board on a card board (like a pizza box board) in the oven;

3.Heat it for 10 minutes (No more than 10 minutes);

4.Turn the oven off & leave the door open, at this moment, do not touch or move the board until it colds down to the room temperature.

5.Install the board in the TV & try it out.