Hybrid failure already? LG42PC1D

[tom66]

Re: Hybrid failure already? LG42PC1D

First, check between 15V and ground, what do you measure?

No short should be present after removal.

Potential locations for caps are indicated in the image attached. Install both with ~47uF 35V devices (Panasonic FM is good here) - but ONLY if +15V and ground measures about 15V.

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

Sorry if its a silly question, do you mean measure it on the bench, out of the tv?

With the board installed it was output 21.3v.

[tom66]

Re: Hybrid failure already? LG42PC1D

Sorry if its a silly question, do you mean measure it on the bench, out of the tv?

With the board installed it was output 21.3v.

Installed in the TV. You were measuring relative to -Vy. Try and measure between the hybrid ground (check if this is the same as the ground across the rest of the TV, if it is, you can use that for convenience, and there might be multiple 15V supplies on this board(!))

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

Tom your on fire here tonight I'll stick back in the hybrid and post back the results tomorrow, thanks again fella!!!

Oh by the way I got a Hisense 32 lcd that has inverter board issues that I hope to pick your brain about as soon as I have this up and running.

[tom66]

Re: Hybrid failure already? LG42PC1D

Oh by the way I got a Hisense 32 lcd that has inverter board issues that I hope to pick your brain about as soon as I have this up and running.

You'll soon be an addict with more TVs than sense! I have not found any other type of electronics that is more unreliable and easy to fix than LCD and plasma TVs. Amazing.

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

You'll soon be an addict with more TVs than sense! I have not found any other type of electronics that is more unreliable and easy to fix than LCD and plasma TVs. Amazing.

My missus would agree, more tv's than sense! But defo addictive, opening all sorts of things that has wires coming out of it!

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

Just looking at a spare y sus from the 50 pc1d board that I have, and on the 18v trace it has 330uf 25v would these do the job?

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

Think i may have found a short in a small diode/resistor? It's placed between the ground and the 15/18v trace, it has a small capacitor above it, once I removed the part there is no short. But i have no idea what to replace it with. Here is a photo of it.

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

It's a 65 35k cap.

[tom66]

Re: Hybrid failure already? LG42PC1D

Looks like 68uF, 35V. Should work fine...

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

Looks like 68uF, 35V. Should work fine...

With out the surfacemount resistor?

[tom66]

Re: Hybrid failure already? LG42PC1D

With out the surfacemount resistor?

Not sure... that little thing would probably vaporise if it were shorted...

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

with the DMM it's shown continuity arcoss it.

[tom66]

Re: Hybrid failure already? LG42PC1D

with the DMM it's shown continuity arcoss it.

How low? Zero?

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

4.6 ohms ?

[tom66]

Re: Hybrid failure already? LG42PC1D

4.6 ohms ?

P = V^2/R = 225 / 4.6 = 48.9W dissipated

That 1/10W resistor would be history!

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

I wish I knew what that means! So do I need to replace that part? And if so how do I know with what to replace it with?

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

Got it working this morning, I have a spare ysus and found 65 if cap with the small resistor below it, put it on as a replacement and she's firing on all four now. However I am taking Tom's advice and going to put on the two caps to the 15v pins.

[tom66]

Re: Hybrid failure already? LG42PC1D

What I am saying is that resistor is probably fine, you are possibly measuring another short circuit somewhere, as otherwise it would be melted very quickly. Like within 100ms.

[caspermccormack]

Re: Hybrid failure already? LG42PC1D

I had the old one out and with the Beeber on (multimeter) it beebed across it, didn't on the replacement and now it's working. Delighted!

And cheers again for all yor help mate, and best of luck in the Euro's!