LG OLED65C9MLB TV green stripe and turns off

Hello, I have a LG OLED65C9MLB SmartTV, and when I press the power button, the standby LED starts to flash, then the green stripe appears, and then the standby LED remains fixed, as if it were off for protection. If I press the power button again, the cycle repeats.
In the attached video, the lines or stripe appear from the top of the panel to the bottom.
The screen has not received any impact.

Can someone tell me if it could initially be due to a fault in the panel itself or in the boards (TCON for example).

It is the first time I have an OLED screen and the dimensions of it limit me a lot.
I have tried to disconnect and connect the flexes, but it remains the same, and visually I do not see any damaged components on the boards

After having performed some tests, when I disconnect the connector (marked in red in the photo) that comes from the MAIN, the TV, although it does not send an image logically, maintains the stable voltages and the standby LED starts to blink as if it were performing the function of turning on and remains on.
As soon as the cable is connected, the TV does not turn on and the voltages rise for a second and the standby LED remains fixed at all times.
I have tried to disconnect the flex cables that go to the panel, keeping the 2 connectors that come from the MAIN connected, but the short or the protection remains and the voltage rises for a second. Only the TV maintains the voltages when I disconnect the cable marked in red.
I have looked for the VGH, VGL and AVV points on the T-CON to measure the values, but they are not present.
The fact that when the cable that comes from the MAIN is connected, the equipment enters protection, could it be indicative that the T-COM is defective?

Hello. Please check the connector (at T-CON) and its flex plug first, whether there are any signs of overload or surge, discolouration, bent or broken tips etc. If both the connector and plug are fine, the T-CON board is most likely faulty - disconnect all cables, remove the black heatsink and post the clear photos of both side of T-CON board.

Hello. I apologize for the delay in posting the photos, but the large size and weight of the TV makes it difficult for me to move it, and so far I have not had any help to be able to manipulate it.
I don't see anything abnormal in the flexes and connectors, everything seems to be fine.

Attached are the images taken with 2 different cameras

In the photos provided, I noticed that the fuses near the power input (marked 65V and 15A) appear overheated. Start by checking if they have continuity using a multimeter. Even if they do, it’s a good idea to replace them, as visible signs of corrosion could affect their reliability and potentially cause problems in the future.

Additionally, measure the voltage and resistance to ground on any of the fuse pins, as they are likely interconnected. It’s important to verify if the power supply to the circuit is stable, which will help with further diagnostics, such as inspecting the T-CON board or the display panel.

I also wonder if the overheated fuses might be a result of an overload in the power circuit for the panel or its controller.

Please post a clear, bright and sharp photos of the area marked with yellow square, best would be couple photos from different angles. As ado stated, this area looks very suspicious.

ado ha scritto:Start by checking if they have continuity using a multimeter

They have continuity and are working.
The voltages remain stable and the TV seems to do the normal boot function, only, while I keep disconnected the connector that is marked in red in post #2.

Vogelek23 ha scritto:Please post a clear, bright and sharp photos of the area marked with yellow square, best would be couple photos from different angles. As ado stated, this area looks very suspicious.

Let's see if these images can be valid

Zemog ha scritto:They have continuity and are working.

A possible reason for the blackened components could be high load during normal operation. To ensure proper functionality, I recommend cleaning these parts thoroughly, inspecting them closely for any signs of damage, and, if they appear intact, soldering them back into place.

Unfortunately, I have had some negative experiences with OLED panels. In most cases I’ve dealt with, the panel itself turned out to be defective. In one particular instance, I encountered a situation where disconnecting one of the ribbon cables (unfortunately, I don’t recall which one) caused the screen to light up in a single spot. That specific area heated up to an extremely high temperature after approximately two hours of operation.

Edit :

ado ha scritto:Additionally, measure the voltage and resistance to ground on any of the fuse pins,

Today, I was repairing two OLED TVs. One of them showed identical symptoms – "after disconnecting the cable marked in post #2," it powered on but displayed a black bar without any content, indicating a clear screen defect.
I’m attaching a picture showing how this area looks in both of my TVs and the measurements I took: 19 V relative to ground and resistance in megaohms.

It is interesting to note that, as you can see, there are two ESD diodes providing protection in the middle section of the pin view, but on the other side, there are also two ESD diodes each. I tried checking the pin descriptions, such as AC Det and others. All signals were present at 3.3 V.