Re: LG 60PV450 - bad Zsus?

Ok, I'm determined to figure this thing out! haha. So pulling back the foam padding on the back side of the zsus allowed me to get a better view of circuitry.

First, I saw that the 3 coils were grounding out which it shouldn't. Pulling back the foam revealed that they are all connected directly to the Collector of those (3) FGPF4633s, which in turn are connected directly to the pins going to the Zsub board.

Looking at the last picture I posted, all Gate to Collectors seemed to be shorting but I found it somewhat unlikely that...

Re: LG 60PV450 - bad Zsus?

I tested it in circuit and it's shorting but i'm sure its because of the surrounding circuitry. I pulled out one and tested it by itself and it tested fine. So now i'm thinking the same thing is happening with those 4633s. Unfortunately the 4633s are attached to a heat sink with another set of 3 transistors. I'd pull them out but my soldering iron sucks and it's not doing a good job of melting the solder.

I may just tell this person to grab a new zsus board. I saw a salvaged one on ebay for $50 but Shopjimmy has them for $65 plus the 180...

Re: LG 60PV450 - bad Zsus?

Looking at the backside of the zsus again it looks like I found a couple surface mount resistors that look a bit brown. They're connected to the gate of a FGPF4633 transistor which I've never heard of. Looking up the Datasheet they describe them as 330V PDP Trench IGBT. Testing them in circuit yields a short between the collector and emitter also but those are also connected together through an RF2001 fast recovery diode. The collectors also go directly to the connections of the Zsub board....

Re: LG 60PV450 - bad Zsus?

There's nothing on the back of the Zsub so im guessing it's fine. I'm just curious as to what's wrong with the Zsus. I'm not sure what happened first, the fuse blowing or the coil coming loose. I'm guessing by the cracked joints that maybe the coil was the first to come loose then blew the fuse but not necessarily instantly.

It's not my tv so I'm not sure what prior symptoms might have appeared before the picture went completely out. I was sure that once i replaced the fuse and resoldered the coils the picture work but it looks like it might've...

Re: LG 60PV450 - bad Zsus?

In the pic showing the backside where the coils are soldered, the one circled is the one that completely came loose from the board. I tested for continuity after resoldering and it seems good. The other two obvious resolders tested fine before i resoldered but it was clear that it was beginning to crack. The remaining looked fine to me.

The Zsub is what the Zsus connects to and contains the flexible printed cables that connect directly to the PDP. There are 3 fixed connectors that connect each board. I couldn't find any test procedures...

Hey guys.. looking for some input on this LG 60PV450 plasma

So, initial problem was there was no picture but sound could be heard. Popped it open and looked around for bad caps, didn't see any, they all looked pretty good. No problem there.

Tested all fuses for continuity, found that the fuse on the Zsus board was blown so I removed and inspected both sides of the board. Found also that out of the 3 huge copper inductors, one of the solder joints came loose along with some heat damage. Moreover, the other 2 inductors seemed to have cracked solder joints.
So I...

Re: New Members - please post your introductions here

Hello! Tons of great information here. So far I've only dug into the troubleshooting TVs section but hope to delve deeper into other areas as soon as I fix the problem I am having..

cheers!