Lg 42LD450 after inserting the software, get stuck in the boot loop

[peraja12]

For the TV from the title (Lg 42LD450-ZA) which was damaged by the motherboard during the thunderstorm, I got the board from China. The board is the same model but for the Chinese area, the Chinese TV model is 42LD450-CA.
The old board and the Chinese are identical, only this Chinese has a different tuner.
Everything worked great, except of course DVB-t because the tuner is different (probably they have a different standard)
The devil did not give me peace so I went to insert the software from the European version (Lg42LD450-ZA), everything went fine, the tv recognized the file, done the right upload, but after the restart tv does not work, only the logo shows, restart and so on in a circle,
Can anything be done, go back to at least Chinese sw, it can no longer be accessed in the menu where sw with usb is installed
The TV responds to the ignition with both the remote and the button (meaning it's not completely dead), but it goes up to the log and restarts ...

[peraja12]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

Didn't anyone have a situation where improper firmware was inserted into tv lg, which caused tv to go into the boot loop, and successfully solved it?

[vinceroger69]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

swap the eeprom ic from the old board onto the new one? although im not sure if this will solve your issue your having hopefully a more experienced member will know.

[Diah]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

The TV responds to the ignition with both the remote and the button (meaning it's not completely dead), but it goes up to the log and restarts ...

the first problem you faced with tuner was easy to fix at service menu

try with service remote or any android device with IR to send command
1-(IN_STOP) reset the set to factory condition
2-(IN_START) to change tuner type and other stuff
3-(E-Z_ADJUST) to change model or serial or region

[vinceroger69]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

lg service remote apk

[cheeky2]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

I would imagine you would have to swop over the tuner module from your defective board to your chinese unit to get it to work in Croatia. Also part of the circuitry maybe different as well examine the two boards carefully alongside each other.
If you wish to put it back again then I would suggest going to the chinese LG site and getting the firmware from there for the Chinese version. Use a web translator to work out the chinese writing. I would use the LG service remote whilst in the chinese firmware to see if you can modify the settings to make it work for you.
Good luck

[Davi.p]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

Yes Chinese uses a different TV signal called ATSC if i remember, the tuner communicate with processor with a serial line, so if you change the main software from a board with an Asian standard/tuner with an European one, this espect to receive specific model data from the tuner i guess. IF you're strong in soldering jobs it is possible to try to swap tuners. But don't advice this since an update is not the full software maybe, is only part containing the modifications since the previous version, since Asian version uses different tv standard it must handle the signal with different software, you probably now have a mixed version Asian/European with conflicts.. Get a new board..

[peraja12]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

This is a similar topic

//www.badcaps.net/forum/showthread.php?t=56571

I tried to connect via rs232 port with hyperterminal but in the prompt it doesn't throw "Mstar #" or "duoglas" but HyperTerminal - BC ^ [^ [^ [^ [^ [^ [^ [
What would this mean?

I have updated firmware and now everything works fine. I used notebook with serial cable and hyperterminal to be able to do this because every other method didn't work for me.

Here is procedure that i followed (copied from other forum):

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

The only difference is that my TV didn't have "Mstar" prompt, after pressing esc it gives "douglas" prompt, everything else was exactly as described here.

[cheeky2]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

Are you certain you have a null modem cable and not a straight pinned com port connection. There is a significant difference make sure you have correct connections for a null modem cable to your pc or laptop (don't use a usb adapter for a com port!).
Good luck

[Davi.p]

Re: Lg 42LD450 after inserting the software, get stuck in the boot loop

It means probably you selected the wrong speed of ser. port.