Hi all. I own a LE40M86BD which in the US is internally comparable to the 65f series and externally to the 61f.
It's been turning itself off, then on, then off, then on for a while but it's now been getting a lot worse. It starts to happen about 5-10 minutes after its switched on. This on/off cycle happens now for as much as an hour and then stops on its own. After the TV has stopped turning itself off then on it works completely fine!
I've read online similar cases and unfortunately they all lead to the same blown capacitor problem. See my pictures in the album but there are no signs of bad caps, the only thing i can see is discoloration on the back of the main board. I just can't see anything in particular wrong.
What could the problem be? When the screen turns off the TV clicks. You see the TV turn off just the same as If you unplugged the cord then power is restored and it comes back on for a few seconds, the picture is shown fine and then once again turns off.
I've tried following another thread on here from someone with the 46 inch version and replaced two commonly at fault SMD caps on the motherboard. I've also desoldered and tested the usual culprit caps on the power board and they all test fine.
The dc voltages supplied to the main board seem fine too. I tested them with everything plugged in while the set is switching itself off/on and apart from the loss of power they all read fine.
I've been trying to run the tv without the motherboard connected by shorting the 5.2v trigger and power on/off pins on the dc voltage cable going to the motherboard but it makes a terrible scratching noise and the screen doesn't turn on. So I can't test if the fault is purely down to the motherboard. (I can get a replacement mb for the tv for £32) does anyone know why this doesn't work?
I also tried to measure the AC input voltage but I can't for the life of me get a reading. I'm not sure why because I can read the dc voltages just fine. I can fit the probes into the connector but just can't get a reading.
Photo album : https://goo.gl/photos/sAt5NG6tQ9wNpJum7
Right now I just want to make sure it's the motherboard at fault and the power supply is okay before buying a replacement board. I'm not sure how to diagnose the existing motherboard so am happy to replace the whole thing.
Thanks for any help.
Dodge
It's been turning itself off, then on, then off, then on for a while but it's now been getting a lot worse. It starts to happen about 5-10 minutes after its switched on. This on/off cycle happens now for as much as an hour and then stops on its own. After the TV has stopped turning itself off then on it works completely fine!
I've read online similar cases and unfortunately they all lead to the same blown capacitor problem. See my pictures in the album but there are no signs of bad caps, the only thing i can see is discoloration on the back of the main board. I just can't see anything in particular wrong.
What could the problem be? When the screen turns off the TV clicks. You see the TV turn off just the same as If you unplugged the cord then power is restored and it comes back on for a few seconds, the picture is shown fine and then once again turns off.
I've tried following another thread on here from someone with the 46 inch version and replaced two commonly at fault SMD caps on the motherboard. I've also desoldered and tested the usual culprit caps on the power board and they all test fine.
The dc voltages supplied to the main board seem fine too. I tested them with everything plugged in while the set is switching itself off/on and apart from the loss of power they all read fine.
I've been trying to run the tv without the motherboard connected by shorting the 5.2v trigger and power on/off pins on the dc voltage cable going to the motherboard but it makes a terrible scratching noise and the screen doesn't turn on. So I can't test if the fault is purely down to the motherboard. (I can get a replacement mb for the tv for £32) does anyone know why this doesn't work?
I also tried to measure the AC input voltage but I can't for the life of me get a reading. I'm not sure why because I can read the dc voltages just fine. I can fit the probes into the connector but just can't get a reading.
Photo album : https://goo.gl/photos/sAt5NG6tQ9wNpJum7
Right now I just want to make sure it's the motherboard at fault and the power supply is okay before buying a replacement board. I'm not sure how to diagnose the existing motherboard so am happy to replace the whole thing.
Thanks for any help.
Dodge
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