RCA 42PA30RQ No Sound, No Picture

[n3lka]

I have an RCA 42PA30RQ with no picture. I get the 2 clicks when powering up and a steady blue led on the front of the tv. I checked my voltages and it looks like my vs and va start at the proper levels and then drop off.

I disconnected power from the x main, no change, and disconnected the y main, no change. With the main connector disconnected from the power supply, I get the same thing, power comes up and then goes back down.

Nothing appears to be hot, burned, cracked, smoked, swollen. Took my meter to most of the devices and everything looks ok.

I saw a couple of threads referring to the led on the main board, my main board doesn't appear to have one, unless I just don't see it.

Anyone ever have a main board go on this model?

I can't edit the title, I just found out it had sound.

[Alastair E]

Re: RCA 42PA30RQ No Sound, No Picture

What chassis is this set using?

A couple of pics can help....

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Thanks for the reply. It's a samsung chassis, but which one, I'm not sure.

I'll attach some pictures.

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

From what I've seen out here after reading multiple threads, it looks like I'll be replacing x and y mains, then upgrading the firmware. Even shopjimmy recommends upgrading the firmware to prevent future failures.

Seems like Samsung and all clone re-sellers should be responsible for paying for repairs or at least order a recall if incorrect firmware is causing failures on a large scale.

When the parts come in, I'll post an update.

[tom66]

Re: RCA 42PA30RQ No Sound, No Picture

Unfortunately, you can't update the firmware on these. As far as I know with these models, firmware isn't a major issue; it's just bad design of the X-main board. You also might only have to replace the X-main board.

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Thanks Tom, I ordered the replacement boards. I was able to get onto RCA's site and get the update. The update is with the color balance. I'll see when I get the boards in.

If it does update successfully or not, I'll let you know.

Brian

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Got the new x and y mains. No change. The power supply keeps dropping off. Wondering if the PS is toast. I can her a noise (oscillation) in the y main, that's when the High Voltage in the power supply drops off. The noise was present on the previous board also

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Pulled the y buffer, power stayed on. Live and learn. Hopefully the y buffer didn't damage the y main. Going to order a y buffer, then try the old mains, then send back the other cards I bought.

[tonyuk]

Re: RCA 42PA30RQ No Sound, No Picture

Pulled the y buffer, power stayed on. Live and learn. Hopefully the y buffer didn't damage the y main. Going to order a y buffer, then try the old mains, then send back the other cards I bought.

have you tried old ones with buffers out i would also try that if they r faulty you dont want to blow new buffers

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

I will try...good thought. There's tons of different replacement #'s. I should get the samsung parts by PBA # correct?

[tom66]

Re: RCA 42PA30RQ No Sound, No Picture

In general these Y-main boards don't blow the buffers when they fail.

[tonyuk]

Re: RCA 42PA30RQ No Sound, No Picture

In general these Y-main boards don't blow the buffers when they fail.

realy ? i was told befor that ysus can blow buffers if faulty

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Well, I tried it with the old boards, and the buffer removed, and the high voltage stayed up. I'll order another buffer and try it with the old boards. So many different versions of that board for this model tv. Shopjimmy recommends using the pba # to match up parts. I see a few out on ebay, time to drain my paypal account a bit more. If this works, at least I can return the other boards for a restocking fee.

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Got the new buffer board, it's bad too. One chip looks like it's bad. Different reading from the other one, but still reading shorts to output pins. Returning it and ordered another one.

[tom66]

Re: RCA 42PA30RQ No Sound, No Picture

realy ? i was told befor that ysus can blow buffers if faulty

Only on the older panels, and most modern Panasonic plasmas.

[n3lka]

Re: RCA 42PA30RQ No Sound, No Picture

Got another buffer from shopjimmy, and used a new y main as well, looks great. No more ebay parts for me, well at least buffers.

[ALittlebit]

Re: RCA 42PA30RQ No Sound, No Picture

I've got a question, how did you find out if there was ever sound? And how did you check the y main to see if it was bad? Also, from what I read should I just go get a good y main from jimmy or should I change the ymain and the ybuffer? Thank you for your help

[lookimback]

Re: RCA 42PA30RQ No Sound, No Picture

I've fixed a few of these. All the ones I've worked on had both the X and Y sustains shorted. Replace only one, and it will instantly become a paperweight.

[lookimback]

Re: RCA 42PA30RQ No Sound, No Picture

I've got a question, how did you find out if there was ever sound? And how did you check the y main to see if it was bad? Also, from what I read should I just go get a good y main from jimmy or should I change the ymain and the ybuffer? Thank you for your help

The Y buffer can easily be tested. https://www.youtube.com/watch?v=51SZsfH60EY

The X Sustain usually only needs two RJH30E2 MOSFETS under the heatsink replaced. The Y-sustain I believe required 4 RJP30E2 MOSFETS and the driver ICs.

Getting sound requires you to use the correct input source, whatever the TV was set to when it went out.

[lookimback]

Re: RCA 42PA30RQ No Sound, No Picture

Got another buffer from shopjimmy, and used a new y main as well, looks great. No more ebay parts for me, well at least buffers.

There's a couple sellers on ebay who are reliable. I've bought a bunch of buffers from TvDoctor with no issues. And then there's Swappart, that's me. I won't sell anything I can't test and something new I just started doing is, whenever possible, making demo videos showing the parts in a working TV.