Dell w2600 lcd tv

[golemmaster]

I'm reposting this in this forum because the repairs newsgroup is talking about everything except electronics.
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Howdy.

I have a DELL W2600 LCD TV.....and it doesn't work reliably. It has a well known problem for this model: After several minutes of use, if you turn the display off and then back on it won't come back on. After many hours Googleing and reading. Lots of reading because lots of people have this problem. There are suggestions and some hints but no solutions. With nothing to loose but the permanent destruction of the TV (I would like to avoid), I have opened it up to see what I can see. Many people seem to think the power supply is the problem. After tinkering and reading an account of someone taking the PS of a known working W2600 and putting it in a nonworking one with no change, it would seem the problem is not the PS. So now I am faced with checking components on the main board. The problem seems to be one of low heat tolerance in a component. Since this model was discontinued fairly soon after production, it is possible that there was a bad batch of components that went into this model.

I would love to figure this out. I will need help.

Calling me a novice would be generous. I know how to solder and check voltages, resistance, transistors and other functions of my multi-meter but that's about it.

I felt the need to tell my story and my limitations before asking my questions.
Hopefully, I haven't driven you off and you are still reading.

I have examined and re soldered broken/cold/dry solder joints. There were some suspect ones on a couple transformers in the PS. I don't see any others. I've replaced a couple capacitors as suggested in some of the Google results.
It would seem the power supply won't come out of stand-by. I think the mainboard is not providing that signal to the PS after it warms up. There is a stand-by pin that normally has 3.3VDC supplied by the mainboard but doesn't when the problem occurs. I've tapped 3.3 from a nearby pin to try to force the PS on but this does nothing.
Most components on the mainboard are surface mount and tightly grouped. It would be difficult for me to desolder them. I'll attempt it if advised to.

Does anyone have experience working on DELL W2600 LCD TV?


Thanks for any help and insight.

 

[Digitalbaron]

Hello Golemmaster, I had a similiar problem with my 37" Polaroids. I bought a broken one on ebay to swap pieces hoping they had different problems. Turned out to be the PS on both. These power supplies to my understanding have voltage and thermal protection and with passive cooling in a stagnant enviornment they were overheating and damaging sensitive thermal protection components ( i can't say which exactly, im not that good.) I mounted a 120mm Scythe ultra silent 33 CFM computer fan to the back and soldiered it into the 12v line out from the power supply, so when you turn it on, it has active cooling and has been working well for over 6 months now. For a test just grab a desk top fan and have it blow directly on the PS and see if the LCD will run. I cut through the back casing and mounted it directly to the internal housing lid. Hope this helps.

 

[golemmaster]

DELL w2600 pic

Here's a pic of what I'm working with. For what it's worth....

 

[wphillips42]

Do you see that wire on the top right of the yellow motherboard in hte picture i need that wire if you fell like selling it if it doesnt work let me know, i cannot find that ANYWHERE! which sucks so if you can please get back to me ill even buy i from you if necessary.

Thanks for the post, and your time.
Mike

 

[neon]

there is a sleep mode just use that

 

[hsiaofei]

A friend of mine has similar problem. When he open the back cover he found there are 2 wires hanging loose. One of the black wire was apparently broke off from the harness. A second wire (white) looks like cut. I wonder if you can send me the picture you took so that I might be able to reconnect the wire back.
Thanks
Sheldon