Magnavox 32md359b/f7 White Screen and with sound only

[YEROC37]

No sign of bulging caps or leaking, Please any advice where to start or any information to look into to narrow this down will be helpful.




above is the service manual

[Mr Bill]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Have you checked all the connectors to make sure nothing became loose? Can you post a picture of the entire back of the tv so we can see what boards are in your set?

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Here are the pictures that I have taken, Thanks very much for your reply Mr. Bill

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

On Jpg 049 I have taken the Capacitor off to test it but reading is ok, but kind of weird question even when I took it off the television still did the same thing. You can see where the cap is missing under the pos/neg wire on middle pic

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

It would not be considered advisable to remove a cap from a circuit and trying to run it without that as it may lead to excessive stress on other components.

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Gotcha, thanks for information tom66, it was a quick on/off. It's back on now and trying to troubleshoot with any advice your site can spare

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Note: I can see very very very lightly the menu selection when I hit that mode button, but it's very dim

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

OK, this means the T-con board, main board and most of the PSU is working. Your inverter, or the part of the PSU which powers the inverter, is the likely culprit.

Try this - Close the curtains, or take the TV into a very dark room. Turn it on. Do you see a brief flicker or flash from the screen, or does it remain dark? It could be VERY brief...

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Yes, It sure does tom66

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

So, the screen flashes briefly? Approx how long - the blink of a gnat's eyelid, or a couple of seconds?

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Like 1--2, Briefly

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

OK, so it is known as "2 seconds to black". This points usually to an inverter transformer failing, or bad CCFL, or bad coupling caps.

Can we have a picture of the back of this board.
https://www.badcaps.net/forum/attach...7&d=1348160962

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I posted pictures above, are those what you need or do you mean other side of board without resistors, caps etc...

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

oh I see what you mean LOL>..duh my bad lol

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Here are the pictures of the back...

[Mr Bill]

Re: Magnavox 32md359b/f7 White Screen and with sound only

If you have a multimeter check the resistance at the ccfl connector on that board. If one is bad the reading will be different than the other 4. Post your results and post a part number thats printed on the side of the transformers.

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

^What he said.

Never seen such a dirty board before. These Magnavox TVs look really poorly made, quite disappointing for a Philips product.

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Yes it does look like a rush job, it's actually not dirty...It's from when they heated the board during the manufac process...but I know what you mean, I currently have the inverter out, do I put this back in to do the reading or where shall I start?

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I'm still fairly new and if you could give me a brief explanation, I'm pretty handy and can probably understand what your telling me. Thanks again

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Set your meter to 20000 ohms or 20 kohms. The ohms symbol looks like a horse shoe.

Remove the board from the TV.

Test across the marked points, using the numbers in the image.

You should get four measurements that are within +/-3% of each other. For example 1030, 1000, 970, 1000, if all transformers are OK.

But if one is bad, it will measure significantly higher or lower than the rest. It could even measure infinite, which will appear the same as holding the probes on your meter apart (usually a single "1".)