Dead LG LCD TV repair

Repair journal | LG 42LV4400 | 47LV4400 | 55LV4400 | 32LV2400
LG 42LV4400-UA.CUSYLH | LCD TV
SYMPTOMS: Dead set. No lights at all.
DIAGNOSIS: This model in particular, along with some other LG have what is called a FLASH IC plate base (MAIN PCB). This is the most common point of failure.
SOLUTION: Replace the FLASH IC for your model. If this is not possible, replace the main PCB for your model. Different affected models and part numbers for your respective MAIN PCB and IC flash bin for each IC code is listed below.

55LV4400
Main PCB: COV31310901
Flash IC: COV31451701
Location: U14
47LV4400
Main PCB: COV31310801
Flash IC: COV31451801
Location: U18
42LV4400
Main PCB: COV31310701
Flash IC: COV31451901
Location: U18
32LV2400
Main PCB: COV31310601
Flash IC: COV31452001
Location: U18
Here are some references of image if you need help to find the Flash IC on the main card:

Attachment 17202
Attachment 17203
As additional advice, be sure to find or acquire a fine tip (wordplay sometimes suck) for your welder. This will make things much easier, believe me. If you are having trouble soldering connections (which are very small connections, trust me on that) it is normal. Best thing you can do is to minimize the time that the welder is put in contact with the workpiece / PCB so that has not been damaged by the heat. If you have a braid of copper as Chem-Wik, it is very useful in the desoldering process. A solder sucker may also work well, but I have found that they have no affinity for the silly welding (just a personal preference). Anyway, good luck and have fun!