Panasonic TH-42PX75X went POP and lost the magic smoke!

[Xtrafresh]

So, this rather large and heavy beast of a TV recently gave off a loud bang, lost the magic smoke, and did nothing more after that. I'm new to doing TV repair, but I'd love to develop some more skills in this area, so i thought this would be a great first project. Having a functional TV afterwards would be sweet, but it's not life or death. I'm starting this thread to get general advice, like:

• needed tools
• parts to replace and where to source
• what are these parts that failed and why?

I apologize beforehand for the bad (phone) pictures.

First, make and model:


So I opened up the back panel, and found no physical damage, not a sign of blown caps (like I suspected). Suspecting the failure to be in the powerboard, I unhooked that and took it out for a closer look:



All seems fine (no bulging caps or anything), until i flipped the thing over:



Clearly these contact points are a little toasty. These 9 contacts are the only ones damaged, everything else looks good. They relate to the components circled below:


So, my direct questions are:
What are these things, and if I could source the parts, will that fix my problem, or will there be other defects I've missed?

Thanks guys!

[stj]

Re: Panasonic TH-42PX75X went POP and lost the magic smoke!

look for the big black soot mark - it may be something under the heatsinks.

nothing goes bang without being very obvious afterwards.

[ReeceyBurger123]

Re: Panasonic TH-42PX75X went POP and lost the magic smoke!

Hello here is a link to a video regarding a fault that sounds like yours: https://m.youtube.com/watch?v=OuykZxLURis

[Alastair E]

Re: Panasonic TH-42PX75X went POP and lost the magic smoke!

Thats just oxidised flux on those 9 points in the picture. Do the parts test as faulty?

Unusual for one of these PSU's to blow up, when they do fail, usually just stop working not make any smoke.--More likely the SC board has let go--They Can and Do go Bang!

[niblettr]

Re: Panasonic TH-42PX75X went POP and lost the magic smoke!

The second photo, capacitor it the top left corner doesn't have a hole in it does it? Hard to tell from photo...

Remove all the boards and look at the chassis. Do you see any signs of residue from damaged component? If not, then you have ruled out the under sides of the boards. On the head sinks, look carefully where the legs of the components leave the plastic bodies (just one example).

[awyatt2]

Re: Panasonic TH-42PX75X went POP and lost the magic smoke!

its a plasma,check the y main and upper and lower buffer boards. probally a field effect transistor (fet) or maybe a cap that popped?. do you have a stby light? it may be related to something other than powersupply.as stj said nothing goes pop without something being visible. look at the square chips on the buffers maybe a hole in one or more, usually they take the y main with them when they go.

[eagle00799]

Re: Panasonic TH-42PX75X went POP and lost the magic smoke!

I have a Th-42PX75U that is completely dead, Both fuses near where the ac power connects to power board were blown along with the mosfet transistor. Those 3 pieces come in a kit sold by many including ShopJimmy and a few on ebay and some kits include those 3 diodes near the fet. Those solder joints indicate that they have been changed and I have done the same thing to mine but when I plugged it in the fet popped with smoke but the fuses did not blow. I pulled the fet out and ordered a new one then compared the reading of both and they were the same so although the fet popped it was still good. I put the new one in and plugged it in and the fet popped with sparks and smoke and this time the fuses blew also. It seems that the pop is coming from the back of the fet and the heatsink. The heatsink does have a square piece of paper?? that sits between the heatsink and fet so not really sure what is going on.