Samsung 60" LED blank screen and WILL NOT STAY OFF

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

Shorted out LED in the series connected LED's will still allow the LED strings to light up, open LED will cause the whole LED not to light up. Too many shorted out LED will also cause the LED circuit shutdown. Shorted circuit in one of the LED string to the chassis will also cause the shutdown.
What kind of the LED strips/assemblies are used in your TV.
I run into panels that have one of the LED strip's wire nicked by the chassis and cause intermittent shorts circuits to the chassis.
BTW, do you have LED tester?

Here is the link to exactly what I purchased from Shopjimmy:

https://www.shopjimmy.com/samsung-bn...-12-strips.htm

So under normal, wall mounted use, what would cause an led to short circuit? When I installed the strips I used strong double sided tape to secure them to the chassis.

Also, if an led is shorted, would it be off or would it still light up? I see no darkspots when the screen is lit and blank.

[budwich]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

you might try further "panel orientation" tests. How about flipping the panel "upside down"... ie. top down, bottom up. Then also try side up / side down. See if things change.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

See if things change.

In regards to resistance on the wires, or in overall behavior?

[budwich]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

overall behavior first.... trying to find a "normal" position (ie. vertical position) where the tv operates properly... then once there you can start checking things to form a baseline along with possibly understanding what the difference is from "proper upright position"... basically, it costs nothing to do the "flips"... and proceed from there carefullly especially with the meters that you have. :-)

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

overall behavior first.... trying to find a "normal" position (ie. vertical position) where the tv operates properly... then once there you can start checking things to form a baseline along with possibly understanding what the difference is from "proper upright position"... basically, it costs nothing to do the "flips"... and proceed from there carefullly especially with the meters that you have. :-)

Tried all different orientations and no change. However, I believe I found where the problem resides, and that is the backlights. While they were on and flashing, I started smelling hot electronics. I smelled around all of the boards and nothing. The smell was coming through the vent hole in the attached picture.

Edit:
I'm preparing myself to open up the panel for the third time.. But I have a few questions for. If an LED itself is shorted, in this particular TV, would the rest of the lights be working and that one would be off, or would it still be on? If it's shorted, can it be desoldered and replaced (I have the original set still)? And finally, if it's a short at the connector between strips, can that be repaired (ie. Electrical tape behind it)?

I'm not up for purchasing a whole new set again as these are out of warranty now.

[nomoresonys]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

Ok, looks like you need to get in there again, wonder if this is one of those models where a problem on the powerboard keeps messing up the backlights or if you have just a backlight short, bare wire, or some such.

[nomoresonys]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

With that burn smell going on, I'm thinking the problem should be visible maybe.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

With that burn smell going on, I'm thinking the problem should be visible maybe.

That's what I'm hoping for. It seemed to be originating from near the bottom center, which it where the strips connect. Perhaps the connector it's arcing on the frame when voltage is applied?

So in the likelihood it's something I can easily repair, what should my expectations as far as life expectancy? I never used them at full brightness, but whatever is happening now makes me fear that their life span has been dramatically decreased.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I think these pictures are self explanatory...

[budm]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

You have bad contact resistance on the connector so it is heated up like that.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

You have bad contact resistance on the connector so it is heated up like that.

Can I repair this or does this strip need to be replaced?

Edit:

Trying to pull the strips back to place something anti-cunductive resulted in the connector falling apart.

Checked eBay and someone wants nearly $20 for a single used strip. So, could I remove the connector and solder wires between the connection points?

[R_J]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I would just remove both plugs and connect them with wires, then make sure non of the connections touch the metal panel. Then also inspect the other connectors while it is apart.
It looks like they had poor solder connections between the plug and the strip, Then it started arcing and burnt the trace. So you might want to resolder ALL the strip plugs

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I would just remove both plugs and connect them with wires, then make sure non of the connections touch the metal panel. Then also inspect the other connectors while it is apart.
It looks like they had poor solder connections between the plug and the strip, Then it started arcing and burnt the trace. So you might want to resolder ALL the strip plugs

Ok I'll do that then.

One of the light spreaders popped off when I was removing the strip. I don't have any super glue, but I do have Loctite SI 595 Clear RTV Silicone Adhesive... Would this work to reattach the spreader? The silicone is supposedly good up to 450°F.

[nomoresonys]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

Funny a brand new strip is of such poor quality, time for a refund on that junk.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

Funny a brand new strip is of such poor quality, time for a refund on that junk.

I know! Unfortunately Shopjimmy only has a 180 day warranty. These are now roughly 14 months old. Should last years longer imo. And they're listing kinda brags about the 'redesigned' connector that is supposedly better.

I know I sound cheap asking this, but I don't have the usual repair items at hand right now, and I really want to just get this thing back together and find it if it works.... But, Clear RTV silicone adhesive.. Can I use it to reattach the light spreader that popped off AND to remount the strip to the inside of the chassis? If not I will go get super glue and double sided tape tomorrow.

[budm]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I would notify Shopjimmy and show them the pictures of the failures and see what they will say.
BTW, I am glad we got down to the cause of the problem.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I emailed them and even stated I knew the warranty was way past. I wasn't really trying to get a free replacement or anything, but damn, their response was essentially "sorry the warranty is expired, we can't do anything. Here's a coupon code for 10% off"
I replied and sent them the pictures and just said I wanted their technical department to be aware of the failure of their product.

Anyway, I just went and picked up double sided tape and super glue, so I'm about to start working on it now. I'll pay a follow-up when finished.

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

After removing the connectors I can see it's burnt straight through down to the aluminum backing. I'm afraid if I solder a wire to it that it will end up arcing or electrifying the entire aluminum strip AND chassis when mounted.

I'm going to try and see if two of my old strips (the originals out of this TV) are will work and probably use them instead. I hate to have to resort to it because they probably don't have that great of life expectancy left in them

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I replaced the strip with one of the original in which i half-ass tested and seen each led blink, but upon reassembly and inspection it is bad. Good news is that upon plugging in the TV it was in standby, and turning it on resulted in a full successful powerup with everything functioning as it should... Except for backlights. So either i coherse SJ into replacing this one strip, or I purchase a used one from eBay :P

[x_orange90_x]

Re: Samsung 60" LED blank screen and WILL NOT STAY OFF

I'm going to have to resort to using a string of the original lights, if I can find a set that works. Is it possible for me to test the Backlights outside of the TV? I seen it done inside of the TV with 9v batteries, but as I said that was inside and plugged in. I bought a bunch of 9v batteries but couldn't get the stands I was checking to light up.

Also, when I have the panel apart, is there a way to trick the LEDs into being on without the panel connected to the tcon?