1) From
http://forum.ixbt.com/topic.cgi?id=62:16479 (russian, translation follows)
To recover an apparently dead lg set you'll need
* a computer with a serial port
* a null modem cable
* a terminal emulation program with file transfer capability (zmodem protocol)
* a good firmware file (*.epk)
* a little care
* a lot of patience
If you don't understand the meaning of anything in this list it's better you call lg service
Warning, incorrect operations could irreparably damage your set
This is the sequence of actions:
1. turn off the tv (by removing the power cable or using the on/off switch, all leds must be off)
2. connect the service port on the tv to the computer serial port with a null modem cable
3. start the terminal emulation program an set the speed at 115200, 8 data bits, no parity, 1 stop bit, no hardware or software handshake
4. turn on the tv and at the same time press Esc on the keyboard. It may be necessary to press Esc more than once
5. if everything goes well, you'll be greeted by a "Mstar #" prompt (here you can write help to obtain a list of available commands in the u-boot bootloader)
6. issue the swuz command (software upload zmodem). the tv will await the file
7. in the terminal emulation program select the correct firmware file (.epk) to send to the tv
8. don't touch anything and hope there's no power cut (it's a long process!)
9. once the file has been successfully transferred, turn off the tv
10. disconnect the serial cable
11. turn on the tv and hopefully it will work
12. dance, sing and think how you can thank tester13a (the author of this procedure)