DP50747 Question

[ad1982]

I had a question about a dp50747-01 Sanyp plasma TV. I'm getting the typical "powers on then relay clicks and it shuts off". I replaced 9 bad caps on the power supply board that now I get a brief flash of the screen before it shuts right back off...it didn't do that before. I'm looking at the 4 led lights on the logic board and am not sure what they mean. They are labeled as D2 through D5. When I initially power it on, they all light up, then all go out but D2. After a few seconds along with the relay that clicks and it powers off, D2 goes out too. I get these symptoms over and over. Any insight?

[ad1982]

Re: DP50747 Question

A quick update to this as I had a couple of details wrong before...it is D3 through D5 that light up and go out, D2 is never lit. Does anyone know what D2 represents?

Also, I've tested the power supply, Vs is getting the correct voltage, but I'm not getting anything on Va at all. I'm still getting a slight flash of the screen each and every time I try powering on. Any suggestions? I appreciate the help!

[newtothis]

Re: DP50747 Question

Ok have a DMM?

[ad1982]

Re: DP50747 Question

No, I only have access to an analog one at the moment. Is there any simple testing I can do with it until I can get ahold of a digital one? Curious what it means when you don't get any reading off of the Va.

[newtothis]

Re: DP50747 Question

Sorry time of night, obviously as you have checked voltages already... < not so obvious!

Voltages at K7H and K7J on PSU?

[ad1982]

Re: DP50747 Question

Let me look around on the board, do you know where abouts I might find these points? Will it be a pin or on a diode or something?

Totally appreciate the help!

[newtothis]

Re: DP50747 Question

Connector from filter board, Throw some pics of the boards and chassis and I will point them out if needed

[ad1982]

Re: DP50747 Question

Here's a picture of the board, I see the points you're talking about, but there are no connectors in place there.

[newtothis]

Re: DP50747 Question

Different revision of board.

Ok lets test voltages on main board for the Power Fail Circuits...

Picture of main board

[ad1982]

Re: DP50747 Question

OK, here are a few pictures that may help. I currently have the power board still mounted, let me know if you need me to get a picture of the full board.

[newtothis]

Re: DP50747 Question

Very hard to see with these pics.

Need them clearer so we can see reference printing on the boards... so good high resolution with good focus.

[newtothis]

Re: DP50747 Question

Its 5 am here and Mrs is moaning about the time so look over these....

[ad1982]

Re: DP50747 Question

Sorry about that, would this one help?

[ad1982]

Re: DP50747 Question

Here's pics of the Ysus, Zsus & the left portion of the power supply board (since it's still mounted in the TV).

[ad1982]

Re: DP50747 Question

Thanks for the reference manual, it looks like I'm getting 5 volts at pin 32 and nothing at pin 36 (if I'm reading that right that I'm supposed to be testing 36 too).

[newtothis]

Re: DP50747 Question

Which connector?

[ad1982]

Re: DP50747 Question

OK, I tested all of the points that were referred to in that manual you sent me, and the only 2 things that didn't come back correct were the pin 36 on the IC801 CPU (pin 32 was correct, and I'm not sure if I was supposed to get a reading on pin 36) and also the D1621 on IC1620 is coming back at about 7 volts (instead of 33v). These were all tests on the Power Failure Circuit page. I did notice that there was no chip in the D1683 spot (on K8B at 12V) but I did measure the little solder pad that was in its place and got about 5 volts (the manual said I should be getting 12V).

I believe I'm testing these right...black lead on ground and red lead on the chip's solder point, like D1621.

[newtothis]

Re: DP50747 Question

Will take a look through when I get back later

[newtothis]

Re: DP50747 Question

Can you take some close up pics of all the connectors on the PSU so i can see the reference labels next to them please

[ad1982]

Re: DP50747 Question

Are you talking about on the foil side or the component side? I'll upload what you're looking for this evening.