Replace main board on LG 42LC7D-UB

When heats up, the supply voltage from the main power supply board goes less. Check all the soldering to this board for any loose solder terminals. Resolder all the suspected solder terminals by applying a little more solder. If it do not help you, replace the board as card basis.

Steve, that was awesome. Thanks a bunch. I already have the tools and I can get the solder easy enough. Thanks a again. I went to Best Buy this weekend and all they could say is that the entire board would need to be replace and that they really recommended a new tv as the cost for the new board would be as much as a new TV.... :( typical of them!

if your are referring to boards the pwr supply and tcon and inveter board will be diff because of size of lcd ,main board might be same have to ck part#'s on board

You need to get exact number from the board: see here
http://www.shopjimmy.com/catalogsearch/result/?q=EBT57840508

You need a new picture tube. They cost about 175.00 and up.

I may put money that some one did stole your internal cable from the power supply to the main board !

Don't be surprised they did it to me at LG company .

The LCD screen is expensive,not uncluding labors yet.Tries check for the new one tv see if worth repairing.Any big screen tv shop in the Yellow pages tech.can replaced it.

Try this place, http://www.shopjimmy.com/catalogsearch/result/index/?q=42lc7d-ub&p=2

I the best place I know of to get parts at a good price.
There are a couple of boards that have different part numbers. You'll have to match the part# with yours. It maybe out of stock, but click on it. Then click on "find other products with this part number". Then all the main boards show up with that part number. A couple of them should be should be in stock.

Most likely the power supply board.

Lie the tv down on a bed and unscrew the back. Its only about 9 screws around the edge and look at the power board, on the left, see if theres any burn marks.

I have a brand new board I bought the other day for the same issue but before I replaced it, stupidly, I checked with LG and turns out mine is still under warranty so I'm stuck with a new board.

Let me know if you want it. I'll match any price you can find online.

There are some inductors that are out of spec. LG's original SB said to replace some of these with a jumper, but it only lasted a couple months.

You need to have the Total Main Assy replaced.