Sanyo DP32628 display turns off

[hairywbush]

Hey guys I'm new. I've read the troubleshooting guide but I am still a little confused so here I am. The most I have done on a tv was replace a capacitor.
On this particular tv, when it's first powered on, the display actually lasts for about 15 seconds then turns off. After that it's only a couple seconds. It's confirmed to be just the backlight. The capacitors are fine and I ohmd them out to be great. I found out it's the backlight inverter from another website, but when I looked this part up, it's not part of my particular tv. So can someone fill me in on what the 2 boards are and what I should do from here?

http://rover.ebay.com/rover/0/e11051...=exe%2cext=ext
this is the part i read about, but even the seller says this tv might not have it. the only thing I see are these 2 boards and then the lcd panel itself.

[hairywbush]

Re: Sanyo DP32628 display turns off

Help?

[ReeceyBurger123]

Re: Sanyo DP32628 display turns off

And what exactly are we supposed to make out from the image ? Seriously can you make anything out ? We need better images before we can help.

[hairywbush]

Re: Sanyo DP32628 display turns off

New pictures for you.

[ReeceyBurger123]

Re: Sanyo DP32628 display turns off

Ok do you have a DMM ?

[hairywbush]

Re: Sanyo DP32628 display turns off

digital multi meter? yes. just let me know if i have to OHM test something which setting.

[ReeceyBurger123]

Re: Sanyo DP32628 display turns off

First check the following:

24v going to inverter, does it stay present ?
BLON & DIM voltages are they present ?

[hairywbush]

Re: Sanyo DP32628 display turns off

like i said I'm new so I am not familiar with your acronyms. is the inverter the green board? where am I testing? There's several connectors.

[budm]

Re: Sanyo DP32628 display turns off

Your pictures only show the main (green) board and the power supply (brown) board, there is inverter board that you do not show in the pictures. You need to show the whole back side of the TV. You need to removed that TV's back cover, this is very badly designed TV hard to get to all the boards when the back cover is removed and hard to power them up too.

[hairywbush]

Re: Sanyo DP32628 display turns off

that's what I was trying to figure out. I tried to see it last night when I had all the screws out but couldn't see another board. I will try again and report back.

[budm]

Re: Sanyo DP32628 display turns off

When you try to lift up the back cover, do it real slow or you will break lots of cables. If I remember correctly , you need to remove the cables from the boards to allow you to freely remove the back cover.

[hairywbush]

Re: Sanyo DP32628 display turns off

I have those cables disconnected, but it looks like there's a screw UNDER the main board, attaching to the lcd case.

[budm]

Re: Sanyo DP32628 display turns off

I do not remember exactly how it was put together, but I remember I cursed a lot and when see them in for recycle, I just do not even bother repairing them any more.

[hairywbush]

Re: Sanyo DP32628 display turns off

I see why man. I did not expect to have to take this this far apart. Speakers unscrewed, board unscrewed, covers... anyway here is where I am at. Still no sign of the board I mentioned in the original post. I think this is all to the back of the screen.

[budm]

Re: Sanyo DP32628 display turns off

https://www.badcaps.net/forum/attach...8&d=1451349933

That is the inverter board, so there must be more than one version of this TV model because the link to the EBAY does not have the same inveter board as yours.
The picture is too blurry for me to read the make and model of the inverter board.

[hairywbush]

Re: Sanyo DP32628 display turns off

sorry it's the only way for pictures for me.
there are 4 rows of numbers
DAC-24T064 AF
2995314700
RDENC2548TPZZ
REV: 01A

On the far left of the board, there is a
LF
LA
tag

[budm]

Re: Sanyo DP32628 display turns off

Sharp RDENC2548TPZZ Backlight Inverter
http://www.shopjimmy.com/sharp-rdenc...-inverter.htm#
Pictures provided by shopjimmy.
So you do have backlights on for up to 15 seconds and then they go out so it means that the inverter board did get the 24VDC to run and the BL-ON (Backlights ON) command signal to turn on the backlights.
The possibility will be that the BL-ON signal from the main board drops out, the 24VDC drops out, the inverter circuit (inverter transformers, MOSFETs for driving the inverter transformer) failed after 15 seconds or so, one of the lamp stop conduction (it only take one bad lamp to cause the inverter circuit to kick into protection shut down), bad black socket contacts where the inverter baord plugged into, bad lamp sockets that has poor contacts.
As you can see, there are many possibilities.
Right now I would check the to see if the 24VDC and the BL-ON (STB pin on the inverter board, > 2.5VDC = ON)) are still present when the backlights go off, if they are present, then that will eliminate the power supply or the main board problem.
The hard part will be having everything all hooked up together to check the DCV.

[hairywbush]

Re: Sanyo DP32628 display turns off

Shame that board isn't available. So you want me to power on the tv and test the board? how will I be testing?I see the STB pin but where would i be putting the ground lead on my multi? I have that inverter board disconnected, the smaller board in the other pic, and i think a ground strap on the main board. Also, that board is only held in by plastic pins. Can I undo these to test the board?

[budm]

Re: Sanyo DP32628 display turns off

So you want me to power on the tv and test the board? What exactly will I be testing? I have that inverter board disconnected, the smaller board in the other pic, and i think a ground strap on the main board.

You will be checking the DCV on pins of the inverter board connector, they are labeled with pin names, you need to check any one of the 24V pin, the STB pin.
All of this has to be done with all the boards are connected back together and powered up. It is not going to be easy.
You can also look at the inverter board real close to see if you can see any section of the board has turned dark brown from the heat.
BTW, you pick the wrong TV to start learning.

[hairywbush]

Re: Sanyo DP32628 display turns off

I reedited my post after looking at the tv again. I was wondering if I could test this board with it unpinned from the tv, because I can see there are electrical terminals underneath.