DYNEX DX55L-150A11 Randomly turns off

[dan armstrong]

Re: DYNEX DX55L-150A11 Randomly turns off

sorry the last post had wrong readings R804 .657 R805 .594 and R806 .605

[freakaftr8]

Re: DYNEX DX55L-150A11 Randomly turns off

Yes. That's way to low to efficiently run power supply.

[dan armstrong]

Re: DYNEX DX55L-150A11 Randomly turns off

Yes. That's way to low to efficiently run power supply.

Do you think I should change all 3 of those resistors ?

[dskall]

Re: DYNEX DX55L-150A11 Randomly turns off

R804 should be 680k, R805 and R806 should be 620k. You can use regular resistors. Do not use one resistor to replace them all. One resistor is not rated for the voltage in that circuit

[freakaftr8]

Re: DYNEX DX55L-150A11 Randomly turns off

Right. Go down to Radio Shack and get some of those half W resistor packs if they still have them

[dan armstrong]

Re: DYNEX DX55L-150A11 Randomly turns off

Right. Go down to Radio Shack and get some of those half W resistor packs if they still have them

Thank You I wish I had radio shack still around my area but they closed up

[Primariochoa]

Re: DYNEX DX55L-150A11 Randomly turns off

DYNEX DX55L-150A11 Randomly turns off

I did a research on the internet about how can I fix my DYNEX DX55L-150A11 55", then I red some posts here and decide to buy a used LCD Power Supply Board Unit, I found 3 on e bay: https://www.ebay.com/itm/162736635194 (this is the link)
So I swapped it and voila! IT WORKED and no more shut offs.

[dskall]

Re: DYNEX DX55L-150A11 Randomly turns off

Glad it worked. Although repair is cheap and easy.

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

What about adding a 10k resistor? And why does my meter read 0.620 instead of 620.0 ohms? Some of my resistors read 68K 68.000 as such and some read 470K 0.470 so I am confused about that.

[budm]

Re: DYNEX DX55L-150A11 Randomly turns off

Do you mean 0.620 with 'K' on your meter display?

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

Yes, I have tested some resistors all that are K ohms and some read 0.620 but others read 62.0 and I am confused as why.

Maybe my meter is bad, I don't know. I think it is possible I am not reading the meter right, it is auto ranging. I will get the El Cheapo meter out and see what I get.

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

So I am getting 1.85 across all 3 resistors not 1.9; lacking .05 so I guess maybe I can add a variable resistor to fix the problem?

[budm]

Re: DYNEX DX55L-150A11 Randomly turns off

0.620 K Ohms = 620 Ohms.
Look at your meter display or post the pictures to show what it is showing on your meter, you should see letter 'K' right on the display.
Just remember one thing, wrong DATA will cause bad troubleshooting.

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

I think the problem is my meter (Mastech MS8221C) It is not showing any symbols such as K or M.
These pictures are a 470K and a 68K resistor

[freakaftr8]

Re: DYNEX DX55L-150A11 Randomly turns off

OK well since we understand what your meter is telling you go ahead and take a resistance reading of all 3 resistors individually and let us know what you get.

My rule of thumb for this power supply design is even if they're reading good replace them anyways if you have the resistors available. Preventative measure. If they're not reading bad they will go bad eventually.

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

R804=0.67 R805=0.60 R806=0.58 But I also have the problem with no 5v standby and I am trying to fix that.

It looks like at least 1 of these resistors are bad.

[freakaftr8]

Re: DYNEX DX55L-150A11 Randomly turns off

Replace r804 w 680k r805 and 806 both way off. Replace those too w 620k. What's your working voltage standing at off the main cap right now?

[budm]

Re: DYNEX DX55L-150A11 Randomly turns off

You need to fix the Standby power supply section first. The PFC IC and the other SMPS IC get the switched VCC from the AUX winding of the STBY power supply.

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

Before the 5V standby went out the TV would shut off. I thought I fixed that because there was some bad solder joints and the TV was working great. About 3 days after the fix the Power Board exploded. The IC A6059H (N901) exploded and took out R905. I may have replaced R905 with the wrong value, does anyone know the correct value of R905? I replaced it with a 1.8 ohm resistor but I am not sure if the color of the second band is grey or black, the original was burnt. Here is a picture of the board on shopjimmy

http://assets.shopjimmy.com/media/ca...1886-top_1.jpg

[Shane711]

Re: DYNEX DX55L-150A11 Randomly turns off

What would cause my 5V Standby to fluctuate? It goes up and down from 1 volt to 5V but will not stay steady.