Magnavox

[mav6759]

I have a magnavox 42MF231D/17 plasma. When I hit the power switch the TV would come on for about 3 seconds and turn itself off with a lot of clicking. I had the TV looked at, at a repair shop and i was told it was the Y board. I'm not sure what a Y board does, but I would think it would have something to do with power board. Does anyone know, if a Y board can cause my issue.

Thanks,
mav

[PlainBill]

Re: Magnavox

I have a magnavox 42MF231D/17 plasma. When I hit the power switch the TV would come on for about 3 seconds and turn itself off with a lot of clicking. I had the TV looked at, at a repair shop and i was told it was the Y board. I'm not sure what a Y board does, but I would think it would have something to do with power board. Does anyone know, if a Y board can cause my issue.

Thanks,
mav

Define 'come on'. Did you have a picture, or was the power led on only for a few seconds? And the answer is yes, the Y-board could do this. Or the Z-board.

PlainBill

[mav6759]

Re: Magnavox

I didn't have the TV hooked to cable or anything, it was a snowy screen for 3 seconds and it turned off.

[mav6759]

Re: Magnavox

Before I buy a new board, is there anything that I can look for on my old Y board, maybe a capacitor or a cap....

Thanks,
mav

[PlainBill]

Re: Magnavox

I didn't have the TV hooked to cable or anything, it was a snowy screen for 3 seconds and it turned off.

Wizard is the expert on this, but as far as I know, this is NOT a Y-sustain problem. This sounds like a small signal board problem to me. Is there any sign of a reaction if you hit the Menu button while the TV is on?

PlainBill

[mav6759]

Re: Magnavox

I can't get the TV to stay on longer enough to hit the menu button. I did take it to a repair shop and the repair shop said it was the Y board. I hope the repair shop new what they were talking about. I just wanted to make sure if it is that Y board is there is anything I kind change such as a cap or capasistor that i can change out.

Mav

[PlainBill]

Re: Magnavox

I can't get the TV to stay on longer enough to hit the menu button. I did take it to a repair shop and the repair shop said it was the Y board. I hope the repair shop new what they were talking about. I just wanted to make sure if it is that Y board is there is anything I kind change such as a cap or capasistor that i can change out.

Mav

When the Y board (Y-sus) fails the cause is often one or more shorted transistors. There are seven of them under the longer heat sink on the left side of the board. The common cause of this failure is one or more shorted ICs on the buffers - the long narrow boards the Y-Sus plugs into.

I would like to point out that a failure of the y-sus usually results in a totally black screen. No snow, nothing.

Coppell TV repair has a blog where he describes how to identify bad buffers. He also sells the transistors to repair the Y-sus board, and explains how to identify the shorted transistor.

Now a little background.

Over 10 years ago I was having problems with my car. It suddenly started running rough, stalling at lights, etc. I took it to a mechanic who called an hour later to say his engine diagnostic said the 'fuel pressure modulator' was bad. The cost was over $400. Having no other options, I authorized the repair. When I picked the car up I mentioned that that must have been the most expensive part that could fail. He replied "No, actually I looked it up, the distributor is more expensive." He DID give me the failed part, and an itemized bill. Included was labor for 'adjusting the ignition timing sensor' at no charge. This caused me to wonder WHY he had looked up the cost of the distributor. And I never took another car back to him.

Several months ago I picked up an LG 42PC3D-UD plasma TV. The guy had taken it to a repair shop, was charged $50 for the diagnosis, and was told the problem was the Y-Sus and Y-buffer. After discovering the repair cost, the owner decided to sell the TV on Craigslist.

After extensive time butting my head, I determined the problem was actually the Z-sus card. This was available for about 1/3 of the cost of the Y-Sus and Y-buffer, and is much easier to replace. Again, I wondered if the repair shop actually diagnosed the problem (I later learned the symptoms of each failure are distinctive), or quoted a high price to pad the bill.

Again, it's your TV, you can do whatever you want, but I would suggest not touching the Y-card until you attach pictures of the set with 'snowy picture' and get a confirmation from wizard.

PlainBill

[mav6759]

Re: Magnavox

Thanks a lot for the replay, I took the TV to a repair shop to have it looked at, I was told it was the Y board. I have one on order and hope to get it in the next couple of days. Now here is my point, I paid this guy a lot of money to detemine the cause of my problem. If it is not the Y board, then me and this guy is going to have a little talk. And I know me I hate for someone to play with my money, so, if it is not the Y board, I don't think this repair guy would this TV up his butt. but I don't have time to play games with these so called repair guys. I here a lot of clicking and the TV does come on for about 3 second with a snowy screen.

[PlainBill]

Re: Magnavox

Thanks a lot for the replay, I took the TV to a repair shop to have it looked at, I was told it was the Y board. I have one on order and hope to get it in the next couple of days. Now here is my point, I paid this guy a lot of money to detemine the cause of my problem. If it is not the Y board, then me and this guy is going to have a little talk. And I know me I hate for someone to play with my money, so, if it is not the Y board, I don't think this repair guy would this TV up his butt. but I don't have time to play games with these so called repair guys. I here a lot of clicking and the TV does come on for about 3 second with a snowy screen.

One thing - you can't just install the Y-Sus and expect the TV to work perfectly. You may get a picture, but you should do the setup on the set for maximum life of the display.

Elektrotanya has the panel manual available here. Unfortunately, it's in Spanish

PlainBill

[mav6759]

Re: Magnavox

I not sure I understand what you mean by seting up the Y board, Is this something in the setup menu of the TV. Also, I am really confused as to the boards in this Tv. There are Y boards, X boards, ABCEDFG boards, I am very confused as to the boards, can someone try to put some light to theses boards.

[mav6759]

Re: Magnavox

I think once you know the boards you have in your Tv and what they do, fixing them would be a little easier

[PlainBill]

Re: Magnavox

I not sure I understand what you mean by seting up the Y board, Is this something in the setup menu of the TV. Also, I am really confused as to the boards in this Tv. There are Y boards, X boards, ABCEDFG boards, I am very confused as to the boards, can someone try to put some light to theses boards.

If you look at the upper right corner of the plasma panel in your Magnavox TV you will see a label that lists a number of voltages - Va, Vs, etc. Some of those voltages are produced in the power supply. Others are produced on the scan cards. Since the voltages require vary with the individual panel, it means the settings on the scan (sustain) cards must be made after the card is installed in the TV.

The closest analogy I can come up with on the spur of the moment is the dwell and timing settings in an automobile's distributor - from the days before cars had electronic ignition. Not only did the new set of points have to be installed, but the gap (dwell angle) had to be set, and the timing adjusted. The car would run if you just set the gap 'by eye', but for best performance the rest of the adjustments had to be performed.

PlainBill

[mav6759]

Re: Magnavox

I'm not sure, if it is the Y board either, I can see the Tv trying to turn on and then turn off after 3 seconds. Something is not keeping the Tv on after 3 seconds its off. But I paid to have it looked at and the repair shop said it was the Y board, but I'm having a hard time believing it.

[PlainBill]

Re: Magnavox

I'm not sure, if it is the Y board either, I can see the Tv trying to turn on and then turn off after 3 seconds. Something is not keeping the Tv on after 3 seconds its off. But I paid to have it looked at and the repair shop said it was the Y board, but I'm having a hard time believing it.

One thing to do before installing the new Y-board: Check the buffers for shorts as indicated in the link in post 7 above.

PlainBill

[mav6759]

Re: Magnavox

Ok i will. I want to find out some information. Is the Y board a power board, and also the guy i brought the Y board from wants the old Y board. That tells me that the board can be rebuilt.. I guess my second question would be can the Y board be rebuilt and if it can, what do you change on the board. I looked at each one of the boards and none of them look bad or burnt.

[PlainBill]

Re: Magnavox

Ok i will. I want to find out some information. Is the Y board a power board, and also the guy i brought the Y board from wants the old Y board. That tells me that the board can be rebuilt.. I guess my second question would be can the Y board be rebuilt and if it can, what do you change on the board. I looked at each one of the boards and none of them look bad or burnt.

There are several possible failures of the Y board. Like many sustain boards by LG Electronics, it has a hybrid. This one has an intelligent design, however, and looks like it can be replaced relatively easily.

The common failure, however are the output MOSFETs. There are (I think) 7 of them in the TO-263 package and they are under the longer heat sink near the output connector. I elected NOT to try to replace them; it looked like a good way for me to ruin a board, inhale a lot of noxious fumes, etc.

PlainBill

[mav6759]

Re: Magnavox

I would have to admit I know nothing about a TV repair. But here is what i do know, I have a 42' Magnavox Plasma 42MF231D/17, that won't stay on. This has got to be a simple fix. The TV will come on, but after a few clicks it turns itself off. Now if I was to break that thought down, something is stopping the TV from staying on but it will allow the TV to turn on. Something is killing that power once the power button is pressed. hmmmm, I see nothing on any of the boards that seems burnt, or any caps are that puffed up. Now to my little knowledge, that only leaves a couple of things, a shout in one of the boards. I guess my question would be which board controls the power to all the rest of the board. I am really confused as tp the boards in a plasma TV. It seems like every board in this TV is a power board. (But that why, does this TV have to connect to a video source before it will stay on.)

[PlainBill]

Re: Magnavox

I would have to admit I know nothing about a TV repair. But here is what i do know, I have a 42' Magnavox Plasma 42MF231D/17, that won't stay on. This has got to be a simple fix. The TV will come on, but after a few clicks it turns itself off. Now if I was to break that thought down, something is stopping the TV from staying on but it will allow the TV to turn on. Something is killing that power once the power button is pressed. hmmmm, I see nothing on any of the boards that seems burnt, or any caps are that puffed up. Now to my little knowledge, that only leaves a couple of things, a shout in one of the boards. I guess my question would be which board controls the power to all the rest of the board. I am really confused as tp the boards in a plasma TV. It seems like every board in this TV is a power board. (But that why, does this TV have to connect to a video source before it will stay on.)

Oh, good Grief!!! Here's a picture of the back of the TV, and most of the boards have been labeled. All you have to do is go to Wikipedia and see what each of them do.

PlainBill

[tmwalsh]

Re: Magnavox

Is "Good Grief" allowed?




heh.
Seems that this board is going to be replaced whether it needs it or not... Wouldn't want to be there when it comes on for 3 seconds. And then goes off.
Don't think I'd be buying and swapping boards w/o doing some voltage checking on my own.
tom

[smason]

Re: Magnavox

Remote.... hmm so THAT'S what the little box with buttons and batteries is...