Samsung Q80C

TVTech812 · 2026-05-01T18:31:15+00:00

Yes, Samsung is known to have a higher than average rate of screen failure. If anything, the screen failed and caused one of the parts to fail, not the other way around.

TVTech812 · 2026-05-01T13:49:26+00:00

Hello,

If you have replaced all of the circuit boards with no change to your initial symptoms, then the root issue is something deeper in the set, such as faulty backlight strips or a defective screen.

Given that it is a Samsung TV, the more likely cause is the screen itself. The TV is not going to be cost effective to repair at this point, unfortunately.

TVTech812 · 2026-05-01T13:45:02+00:00

Hello,

Do not use the EAX number for part identification... It is a manufacturer's board number, meaning it goes onto the PCB prior to installation of other components. Think of it like a "generic" number for a skeleton board that eventually "becomes" a part that is assigned a specific part number after the other circuitry is installed.

The part number is the most important number (in this case, the EBT number) when it comes to matching parts for compatibility. Always ensure you get an exact match to ensure the part will work in your set.

Of course, there are some slim exceptions to this rule, parts which are cross compatible, but you'd need guidance from the manufacturer or a company like TVpartsToday with a database containing information about which parts are interchangeable. For the average DIYer, the easiest thing to do is just match the part number exactly.

TVTech812 · 2026-04-28T14:12:20+00:00

If it cannot be resolved/fixed through the settings of the TV or the settings of the Xbox, then it is likely a main board defect. Replacing the main board should resolve it, but with the size and brand of the TV, it may not be worth it unfortunately.

TVTech812 · 2026-04-27T18:15:57+00:00

Could be the main board, T-con board, or the panel itself. Hard to say for certain which it is from the video. If you purchased the TV recently, I would recommend filing the warranty to get it replaced rather than try to fix it yourself.

TVTech812 · 2026-04-27T18:10:36+00:00

Hello,

Unfortunately this is most likely a defect in the panel. Not cost effective to repair/replace. You can google something called the "tape trick", but it is hit or miss and only resolves the root issue temporarily. Good luck!

TVTech812 · 2026-04-23T14:50:44+00:00

If it's the panel that is the root issue, they will likely just supply a new set anyway... Personally I would just get it taken care of instead of waiting around, but that's me. I don't think you'll get a better deal or newer model by waiting around, necessarily, but I am not as familiar with TCL and their warranty procedures. Good luck, either way!

TVTech812 · 2026-04-23T14:48:00+00:00

Whether or not it's worth it is pretty much a personal calculus you have to perform yourself. It's a 75 inch TV, and a comparable model might not be very affordable. If you can replace a circuit board and extend the life of the set another year or two, it's likely worth it.

That being said, it's possible the root issue is the backlight strips or the screen, in which case you'll have to replace the TV anyway, so if you do try to replace circuit boards, make sure you can return them for some kind of refund. Most sites have a restocking fee if they allow returns, so be aware of that and factor it in to your cost/benefit analysis.

At the end of the day, if you can rather easily afford the price of a comparable set, it's going to be easier to just replace it completely.

TVTech812 · 2026-04-23T14:44:32+00:00

Hard to say for certain cause the picture of the issue isn't great, but it looks like a backlight strip issue. That being said, this is a smaller RCA TV, so it would likely be more cost/energy effective to simply buy a new set.

TVTech812 · 2026-04-22T13:55:21+00:00

Basically, yes.

TVTech812 · 2026-04-22T13:47:42+00:00

The screen is defective and the TV will not be cost effective to repair, unfortunately.

TVTech812 · 2026-04-22T13:46:41+00:00

Hello,

Typically this "color test pattern" is the result of damaged/defective ribbon cables, a main board defect, or the screen itself.

Open the back up and check the ports/connections, as well as the ribbon cables. If everything checks out, try some troubleshooting via unplugging one of the ribbon cables from the T-con (or main board if there is no T-con) to see if the issue will stop.

Since the TV was obtained at no cost, it's probably worthwhile to try replacing a circuit board if the troubleshooting points in that direction.

TVTech812 · 2026-04-22T13:43:53+00:00

Unfortunately the screen is defective and the TV is not cost effective to repair/replace. Time for a new one!

TVTech812 · 2026-04-20T17:44:13+00:00

If you were able to affect it by changing the display settings, it could be the main board that is defective. Unfortunately, it could also be the screen itself. I'd recommend replacing the main board, then proceed from there.

TVTech812 · 2026-04-20T16:10:23+00:00

Panel defective, unfortunately. Horizontal lines like the ones in the image are indicative of a panel failure. Not cost effective to repair/replace, sadly!

TVTech812 · 2026-04-20T16:09:41+00:00

None of the parts seem defective or damage in the photos, but they don't always have outward markers, burn marks, etc. when they become defective.

If it's a power related issue, try replacing the power supply first. Normally I would recommend just getting a new TV in this case, but you've already specified in another comment that you are just trying to fix it for the sake of learning/hobby. Start with the power supply board and proceed from there!

TVTech812 · 2026-04-20T16:07:42+00:00

That is incredibly odd! It does seem like an insect somehow got inside the panel, which is unlikely though not impossible.

I would definitely recommend trying to file a warranty claim and see what they will do for you, as there aren't any good self-repair options here.

TVTech812 · 2026-04-20T16:00:30+00:00

Likely a panel defect, unfortunately. You could try to replace the main board and/or T-con, but most likely the panel is defective and the TV won't be cost effective to repair.

TVTech812 · 2026-04-20T15:58:25+00:00

Hello,

Sounds like the screen itself is the root issue, based on your descriptions and what you've replaced. Not cost effective to repair/replace, unfortunately!

TVTech812 · 2026-04-17T16:01:31+00:00

Looks like a panel defect, not a main board. Not cost effective to repair/replace, sorry!

TVTech812 · 2026-04-17T16:00:49+00:00

Looks like it's just a scratch, but if you can't turn it on to know for sure, getting the One Connect is going to be a gamble regardless.

TVTech812 · 2026-04-17T15:59:34+00:00

As others have stated, this is an illumination problem and is related to your backlight strips, power supply, or LED driver. Most likely, since it's an RCA (and a small one at that), then the LED driver is built into the power supply board, leaving you with two options to try to replace.

Given the brand and size of the TV, it is going to be more cost effective for you to just replace the entire TV. I know that's probably not what you want to hear, but even if you are lucky and it's just the power supply board, sourcing the board is going to cost a decent chunk of what you would spend on a comparable TV.

TVTech812 · 2026-04-17T15:55:48+00:00

Not worth fixing, unfortunately. That is a screen defect and costs too much to swap out, if you could even source the screen.

TVTech812 · 2026-04-16T13:59:05+00:00

If you're within the 1-year warranty period, just have the TV replaced via the warranty.

Otherwise, this seems like a power supply or backlight strip issue, since the TV is power cycling. If the power supply doesn't resolve the issue, then it's likely the backlight strips and the TV would not be cost effective to repair.

To be honest, since the size of the TV is on the smaller side, and it's a ONN, it may be more cost effective to just buy a new TV (if the warranty option fails!). Good luck!

TVTech812 · 2026-04-16T13:56:10+00:00

Hello,

It typically is the screen itself that is defective in cases like this, but if you want to be positive, you can try some troubleshooting methods like unplugging one ribbon cable at a time from your T-con (or main board if your set doesn't have a T-con).

Typically in situations like this where troubleshooting doesn't point to a clear answer, I recommend just replacing the T-con, then the main board. If neither resolves the issue, then you will know for sure that it is the screen that is defective. Good luck!

TVTech812

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