LG 42" 42LD550 start up.

[Pukehead]

Re: LG 42" 42LD550 start up.

ok, will do.

[nomoresonys]

Re: LG 42" 42LD550 start up.

Good video there on testing voltages and voltage regulators etc: https://www.youtube.com/watch?v=ocqnqmBxiqY

[Pukehead]

Re: LG 42" 42LD550 start up.

I got 1.4 Kohm.

Also, last night i tried to update the software. I plugged in the USB stick and nothing happened. I went to bed and when i got up, The backlights were on and the red led was steady. TV appeared normal.

I turned off the tv, unplugged the USB stick and turned TV back on. Same issue.... no backlight, led pulsing.

[nomoresonys]

Re: LG 42" 42LD550 start up.

Did you do some of the testing in that video, voltage regulators etc?

[nomoresonys]

Re: LG 42" 42LD550 start up.

Probably the same old problem with the bad bga in the LG tvs, could try heating or cooling the bga then plug tv in and see if it trys to work or anything.

[Pukehead]

Re: LG 42" 42LD550 start up.

Yes i did all that early testing.

I tried heating up the board with a hot air station. Just not sure where it needs the most heating. IE what IC/ SMD?

[nomoresonys]

Re: LG 42" 42LD550 start up.

Guess we need those good clear straight shot pictures of the whole back and each board.

[diif]

Re: LG 42" 42LD550 start up.

Yes i did all that early testing.

I tried heating up the board with a hot air station. Just not sure where it needs the most heating. IE what IC/ SMD?

The main processor, under the big heatsink in the middle.

[Pukehead]

Re: LG 42" 42LD550 start up.

The main processor, under the big heatsink in the middle.

Ahh. That one. That thing runs hot even in STBY mode. Should i take the sink off it to heat it up?

[diif]

Re: LG 42" 42LD550 start up.

Yes, take it off.

[Pukehead]

Re: LG 42" 42LD550 start up.

Ok i will try that tonight. Do you know what adhesive is under it in case it doesnt stick back on?

[diif]

Re: LG 42" 42LD550 start up.

Ok i will try that tonight. Do you know what adhesive is under it in case it doesnt stick back on?

Yes, a few adhesives can be used, I wouldn't worry about it for now, there is a possibility the processor is already dead.

[nomoresonys]

Re: LG 42" 42LD550 start up.

Big problem if the bga is hot in standby.

[Pukehead]

Re: LG 42" 42LD550 start up.

So i tried heating up the main chip. Back-light works but i get no menu, sound or anything that resembles an input signal. I ordered a used board off the bay. Hope it works. I'm also going to try and cool the chip better maybe a bigger sink or a fan.

[Pukehead]

Re: LG 42" 42LD550 start up.

Thanks guys for all your help.

[nomoresonys]

Re: LG 42" 42LD550 start up.

Cool, let us know how it goes.