VIORE 32" - Power board problem?

[sansonet]

At least I think it is power board. But I could be wrong. TV - VIORE LC32VH56, symptoms - upon plugging in, green power light comes on and stays on, no blinks, etc. But nothing else. I can't even turn it off, pressing power button doesn't do anything. I have component tester so I unsoldered and tested all caps. They little lower than specs, but withing 20% limit, most not lower than 10%. Tried 24V light bulbs in 24V output - nothing. Multimeter doesn't show any power too. I'm attaching pics of power board and main board. Is there anything else I can test to find a problem?
If nothing else, I could buy used power board to replace it, they are not very expensive, but I want to be sure that will fix a problem before I'll spend money on it.

[newtothis]

Re: VIORE 32" - Power board problem?

Read 5v at any of the pins from the connector that goes from PSU to main?

[sansonet]

Re: VIORE 32" - Power board problem?

In reference to first picture, main board connector (CON4) from left to right:
1. GND
2. GND
3. 0.32V
4. 0.32V
5. PS-ON -2.75V
6. +5VSB - 5.16V
7. 0.32V
8. 0.32V

no reading on rest

[newtothis]

Re: VIORE 32" - Power board problem?

Do you have a resistor between 470ohms and 1K?

[sansonet]

Re: VIORE 32" - Power board problem?

Do you have a resistor between 470ohms and 1K?

To replace it on power board? You think it got bad one? I have component tester and can test it if I know which one to test. If it need to be replaced, I can try to find one. I have some old boards and I can see if it got resistor like this, or I can buy one.

[newtothis]

Re: VIORE 32" - Power board problem?

No, its so we can jump the PS-On and 5v Standby pins on the PSU to see if its the main board at fault. An old one of a board will work as long as its between those specs

[sansonet]

Re: VIORE 32" - Power board problem?

OK, I'll try to find one tonight. If I do, what I should do with it and how can I detect if board is at fault?

[newtothis]

Re: VIORE 32" - Power board problem?

Well would guide you if you found one that is ok to use... What we would be hoping for is for the backlights to come on.

unplug the TV

Would need to disconnect the PS_ON cable from the mainboard (so using a pin can remove it from its connector or cut the cable - just make sure there is enough cable to connect it back up) Leave the rest of the connections in place.

Jump PS_ON to the +5VSB using a resistor between 470ohms and 1Kohm

Plug set in.

i have a feeling the Main is at fault and is holding the PS_ON signal wrong.

[sansonet]

Re: VIORE 32" - Power board problem?

Ok, I can't do this now, but I'll try to find this resistor tonight and I will get back here when I do.

[budm]

Re: VIORE 32" - Power board problem?

"5. PS-ON -2.75V" Main board is supplying 2.75V which is enough for the Power supply to come on. So you need to troubleshoot the power supply board.
BTW, there are no label on the pins for the BL_ON and DIM signals?
Whole pictures of the top side and the bottom side of this power supply board?

[tibimakai]

Re: VIORE 32" - Power board problem?

I have worked on only one 32" LED Viore TV, but my experience with it, it was bad solder joint(s).
Worth checking the solder joints. Worst soldering job, that I have ever seen. It was done manually, by some beginner!!!

[sansonet]

Re: VIORE 32" - Power board problem?

OK, I found this one - it shows about 810 ohm in tester. Should I use it?

[sansonet]

Re: VIORE 32" - Power board problem?

I just tried it, not sure if I jumped it correctly, but TV acted without changes, still just green light on and nothing else.

[sansonet]

Re: VIORE 32" - Power board problem?

BTW, there are no label on the pins for the BL_ON and DIM signals?
Whole pictures of the top side and the bottom side of this power supply board?

No, I don't see such labels anywhere on the board. Here are top/bottom pictures

[philliesfan30m]

Re: VIORE 32" - Power board problem?

did you check d2 and the other 1 by j10 on the heatsink they both look burnt or bad solder joints compared to the other 1

[sansonet]

Re: VIORE 32" - Power board problem?

Yes, they connected, I checked with continuity tester and with component tester. They don't look as good and have left over solder paste because I messed it up a little when I removed heatsink to get to caps. There row of 6 cups right under heatsink and it's is hard to get them out without removing it first.

[philliesfan30m]

Re: VIORE 32" - Power board problem?

was this your tv or did someone else mess with it at all? and that 47uf50v cap on our mainboard is that just rust or some crap on the back of the cap or did it explode? so when you plug the tv in it tries to power right up? it doesn't go into standby mode and when you push the power button it doesn't do anything?

[sansonet]

Re: VIORE 32" - Power board problem?

Caps on mainboard are OK from what they look like, but I didn't test any of them. That 47uF cap is OK too, it just got some of that red adhesive they used around screws. I don't think somebody else "messed" with it, it was given to me because it doesn't work so they gave it away. TV not "tries" anything at all, only green led comes on and stays on. No reaction on power button or any other, it have to be unplugged to turn it off.

[philliesfan30m]

Re: VIORE 32" - Power board problem?

what about the wiring going to the power button on the front of the tv? did you look at that? and where does that connect on the power board? it should go into standby not right on which is the green light it should be red first i believe

[philliesfan30m]

Re: VIORE 32" - Power board problem?

even so it still isn't turning on and showing a backlight and picture. does it have sound or no? did you check just the caps or did you check the diodes and mosfets?