Samsung XL2370HD 23" LCD TV pink screen then powers off

[TorqueMaster]

Samsung XL2370HD 23" LCD TV pink screen then powers off.
Mfr date Oct 2010 Used ~4-6 hours daily ~ 6 years

I searched for my model and found little. Searched for my symptoms and found more, but still not sure where the issue lies I found a replacement power supply board for $32 (pull) or $45ish ("refurbished") but not sure that's the problem. I'll try component level repair if it comes to that but at those prices, prefer to swap a board and be done with it. If used/refurb parts are to be trusted. Not yet sure what a main board runs or even if available.

Here it is:

After sitting unplugged a long time, powers on ok, responds to remote, picture, sound, tuner all working fine. After 30-60 seconds, sound is gone and screen turns light pink with white spots/stripes in fairly regular pattern. After a few seconds, screen goes dark. Have to unplug to get it to restart. Picture/sound/tuner/remote work for a few seconds, then same pink, same dark. Unplug to restart, just get pink, then dark. I think I can always unplug and get pink/dark after that.

I looked at the power board, but see no visibly blown components or bulging caps, or burnt traces, or cold solder joints. Rats. 8? legged transformer looks a little cooked, maybe.

Main board looks like it may have gotten wet on one side of the board (no clue how or when, it's one owner, well treated) due to orangish rust on some traces, and whitish residue. Otherwise, same as power board, no obvious signs of physical damage.

Appreciate any tips on verifying which board/component(s) to suspect. Clean the rust/residue off? With what? Cold spray certain components?

If it comes to component level repair I'll happily attach photos of everything. Hopefully the description of the failure mode will be enough to diagnose...?

Thanks for any suggestions!

[budm]

Re: Samsung XL2370HD 23" LCD TV pink screen then powers off

We need good clear pictures of the screen shot to see what the pictures look like, then we need the pictures of the whole backside of the TV so we can see all the boards and how they are connected together, and the pictures of the 'orangish rust on some traces, and whitish residue.'
BTW, do you have proper tools for the repair works?

[TorqueMaster]

Re: Samsung XL2370HD 23" LCD TV pink screen then powers off

Photos attached. I circled connectors.

Failure mode has changed slightly. Now the tv will work ok, then show 1 - 3 of the video freeze styles shown, go black, then turn back on and repeat the cycle. After half a dozen cycles it went black and stayed off.

All freeze photos are of static images, nothing is moving. The color of the freezes varies with what was on screen when it froze. These three were not in succession, not from the same failure cycle. It goes in order freeze1, freeze2, freeze3, black, but any 1 or 2 of the steps may be omitted before it goes black.

I have a phillips #2 to swap boards.

I have a 40W iron, solder, solder sucker, solder wick, various small tools, basic multimeter (V, A, Ohm.) Have experience with desoldering and soldering larger components (resistors, caps, etc) but don't try on the tiny surface mounted stuff.

[budm]

Re: Samsung XL2370HD 23" LCD TV pink screen then powers off

I would have to say it is n=main board problem.
I cannot tell if those stains are flux or not. You can use 90% (or higher) isopropyl alcohol for cleaning the residue.
Also make sure all the boards mounting screws are tight.

[TorqueMaster]

Re: Samsung XL2370HD 23" LCD TV pink screen then powers off

Thanks for the advice.

Is it likely heat related, since it takes a shorter length of time on each consecutive restart, before it stays off? Can I spot blast main board components, and see if any improve duration?

I've seen flux residue and am pretty sure this is not.

I'll try a cleaning and check the screws.