Re: JVC Plasma GM-P420UG (won't come on)



I found some better pictures of the boards.......

Re: JVC Plasma GM-P420UG (won't come on)



That's what I was hoping when I swapped out the X Main board with a known good one... but no luck... same problem. The PS shuts down...but stays up as long as the X Main is not connected to the PS.

The X Main board does connect to the Relay Recover Board and Signal Relay Boards. I suppose I could disconnect them from the X Main and see what happens.

My theory today was maybe the X Main board is just too much for the PS due to leaky caps however now that I remember, I tried disconnecting the Y Main board...

Re: JVC Plasma GM-P420UG (won't come on)

Ok, I'll check.

The thing is... the PS stays up as long as the X main board (which has been replaced yesterday) is unplugged. If I had a shorted fet in the PS, wouldn't it stay down no matter what?

Re: JVC Plasma GM-P420UG (won't come on)

The owner decided that he didn't want the set anyway so I have adopted it.

I'm just gonna change out all the caps in the PS and see what happens... except for the 2 big ones.

I went ahead and bought one of those Blue ESR meters from Anatec too... for the next flat screen, I guess. I already have a Fluke with a cap checker but it doesn't do in-circuit checks. After reading more of this forum, I have a feeling I'll be seeing more leaky caps in the future.

After reading thru the JVC service manual, I...

Re: JVC Plasma GM-P420UG (won't come on)

Thanks for the info.

Here's a picture of the PS and X Main boards....

Re: JVC Plasma GM-P420UG (won't come on)

Ok, will do.

It isn't my tv so I'm not sure what happened before it stopped working. As it is now, the status led will switch from green to yellow when the power button is pressed. I hear a relay click but that's about all.

I pulled it apart to check the power supply.... no obvious swollen caps. When I plug in the power cord, I hear the switch mode supply come up and then go down a few seconds later. I measure 5v on the supply line at first and then it goes to .9 or .6 and stays. On this model, the board on the left is called the X Main Board. I noticed that when I unplugged it from the PS,...

Re: New Members - please post your introductions here

Greetings,

I found this forum after searching for info on a Plasma set that fell into my lap. I haven't been doing tv or vcr repair since... about '97. I'm still doing repairs but on more of an industrial electrical/electronic level. Well... except for stuff around the house.

Anyway, the flat screen LED set at work broke and I was able to fix it by just replacing the caps in the switch mode supply. Oddly enough, not much longer after that, the Plamsa screen in the owner's office went up so now I'm...