LG 32PC5RV Dead

[smason]

Hi all, been busy haven't been on here much. But I thought I'd scrap what I should be doing and have a go at a plasma TV

Got this not too old Plasma from a business associate, who got it and a dead monitor from a client. The story as I remember it, the owner called service as it was under warranty, tech came, said it needed a main board, called it in and someone (store, warranty company, LG?) said they'll replace the set.
He got a new one, and got to keep the dead one.

So, plug it in, turn it on green light flashes for 9-15 seconds or so then goes red.
This is my first plasma, so I'll be in n00b mode

5vsb is fine. 5v on the connector that goes to the YSUS board is 5v for a few seconds every so many power on attempts, but never for long, otherwise it's .8v or less. If I unplug the YSUS, it goes green and 5v is 4.9ish steady. The 2 5V pins on the cable that goes to the Ysus measure 1.something megohms to ground, so doesn't seem shorted.

With the YSUS disconnected and the TV powered on, the Power supply will light both elements of an 1157 bulb which draws a measured 1.5ishA on the 5V out to YSUS connector. Not a great test but all I had this evening.
How much load should I put on the PS to test?

Now, what confuses me is ZSUS. There's no board marked as such, but there are 3 pins on the top right connector on the power supply labelled zsus, and there is a ribbon cable coming out of the power supply board to the panel.
So is this board also a ZSUS, or am I missing something?

I'll try to get better photos when I can set it up in some light.

[PlainBill]

Re: LG 32PC5RV Dead

OK, it looks like they have combined the power supply and the Z-Sustain. The main board and the main logic board also seem to have been combined.

The symptoms would seem to indicate a problem with the Y-sustain, while the history would indicate the main board. Of course, the history is hearsay. I have a couple of suggestions. the first is simple and should be safe. Hook up a signal source (one that includes sound) and step through the inputs until you hear the sound. The service manual is on Elektrotanya, but it's REALLY short.

PlainBill

[smason]

Re: LG 32PC5RV Dead

Will try that this evening.

On my way out the door this morning it occurred to me to check the 2 fuses on the YSUS. The top one is open.

[smason]

Re: LG 32PC5RV Dead

Ok, powering on with ysus unplugged an an audio source hooked up, I can toggle through the inputs, and get sound. Volume control works.

I suspect that means the main board is probably OK.

Will remove the YSUS and test some components next.

[smason]

Re: LG 32PC5RV Dead

Removed YSUS and had a good look at it. I'm assuming the buffers are on this board (remember this is my first Plasma) that's what it looks like to me.
No hybrids (is that good?)

The board is very clean, no spots that look like they've been hot. All buffer chips look good under magnification (no burn marks, pinholes..)

Several of the 3 terminal devices on the heatsinks measure shorted in circuit.
3 FETs and 2 diodes.

These include D502 D505 (RF2001) Q506 Q510 (RJP6065) and Q512 W9NK70Z

[smason]

Re: LG 32PC5RV Dead

The W9NK70Z looks easy enough to find, the RF2001 is a T4, I see T2 and T3 on the internet no T4s. And not much luck on the RJP6065 so far....

Some photos:

[smason]

Re: LG 32PC5RV Dead

Oops, I lied. Digikey has the RF2001T4S

[smason]

Re: LG 32PC5RV Dead

Soooo, what are the chances that the buffers are ok?
Or if I find these parts replace 'em will I watch them go "pop"?

[PlainBill]

Re: LG 32PC5RV Dead

Soooo, what are the chances that the buffers are ok?
Or if I find these parts replace 'em will I watch them go "pop"?

It depends on the cost of the parts. This place claims to have the board for $59, and they are on your side of the border.

PlainBill

[smason]

Re: LG 32PC5RV Dead

It depends on the cost of the parts. This place claims to have the board for $59, and they are on your side of the border.

PlainBill

Wow, great find! Thanks.
Might be worth $60.00

[smason]

Re: LG 32PC5RV Dead

It depends on the cost of the parts. This place claims to have the board for $59, and they are on your side of the border.

PlainBill

Yeah, not getting a warm fuzzy feeling from them. Called the phone number, a woman with a very hard to understand accent answered.
After a few attempts to understand what she answered, I asked "Is this HD World?" "Uhh Yes"
Hi, I'd like to order part number "blah" do you have it in stock.
Her "umm yes we have, um wait.. Manager not here, he call back"

So I get a call the next day as I'm driving home. "Hello, my wife say you looking for part, yes? "Yes, if you have it in stock, and it's the exact number I gave, then yes, I'd like one"

Some more delays, then he asks where I am, I tell him, and he says he can ship Canada Post. Fine. But then he says they can't do credit cards or Paypal. Only direct transfer to bank, I give you account number...

Sure, that doesn't raise any red flags...

I say, email me, I'm in my car and can't write it down.

Still no email a week later...

Saw one on Ebay in Quebec, but $80.00 plus $20.00 shipping is more than I want to put into this TV....

[PlainBill]

Re: LG 32PC5RV Dead

Too bad about that one. I can understand not taking credit cards. But heck, even I accept Paypal. That certainly would not give me a comfortable feeling.

PlainBill