It may be a that it is a faulty audio amp circuit in the TV although this doesn’t really explain satisfactorily why there is intermittent audio only in the headphones and not the main speakers as well.
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''The first possibility'' is a faulty headphone jack.
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Not sure as the [https://servlib.com/lg/tv/47le5500-47le550n-47le5510-47le5800-47le5810-47le5900-47le5910-chassis-ld03e.html?start=0|service manual] doesn’t show it that well but with headphone jacks depending on the type they operate in one of two ways.
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The first way is that there are two internal “break” contacts that operate when the headphones are plugged in. This disconnects the audio from the main speakers and it is connected to the headphones. Given that you said that there is intermittent audio in the headphones it may be that the contacts in the jack are dirty or faulty or even a dry joint solder connection for the jack.
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The second way is that there is an internal single “make” or “break” contact that operates when the headphones are plugged in and this signals the audio controller to disconnect the audio from the main speakers and to direct it to the headphone jack.
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For either type I can see that it could ''possibly'' be causing the problem.
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''The second possibility'' is that it is a faulty audio amp circuit in the TV although this doesn’t really explain satisfactorily why there is intermittent audio only in the headphones and not the main speakers as well.
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Here are some poor images (apologies) taken from the service manual that show that the audio is fed out of the TV’s CPU to the audio amp and then to the speakers and that the headphones have their own amp.
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Here are some poor images (apologies) taken from the [https://servlib.com/lg/tv/47le5500-47le550n-47le5510-47le5800-47le5810-47le5900-47le5910-chassis-ld03e.html?start=0|service manual] that show that the audio is fed out of the TV’s CPU to the audio amp and then to the speakers and that the headphones have their own amp.
[image|2151613]
[image|2151612]
(click on images to enlarge for better viewing)
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Sorry to be so vague but the TV will have to be opened and the problem further diagnosed as to the cause. Hopefully it might be the headphone jack but if not then it is on the mainboard.
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Sorry to be so vague but the TV will have to be opened and the problem further diagnosed as to the cause.
Note: The service manual can be used online. It is awkward however as you have to select the page number at the bottom below the document box every time that you wish to turn the page. To download it you need to register with the website.
Hi @mcstringer ,
Two possibilities come to mind.
''The first possibility'' is a faulty headphone jack.
Not sure as the [https://servlib.com/lg/tv/47le5500-47le550n-47le5510-47le5800-47le5810-47le5900-47le5910-chassis-ld03e.html?start=0|service manual] doesn’t show it that well but with headphone jacks depending on the type they operate in one of two ways.
The first way is that there are two internal “break” contacts that operate when the headphones are plugged in. This disconnects the audio from the main speakers and it is connected to the headphones. Given that you said that there is intermittent audio in the headphones it may be that the contacts in the jack are dirty or faulty or even a dry joint solder connection for the jack.
The second way is that there is an internal single “make” or “break” contact that operates when the headphones are plugged in and this signals the audio controller to disconnect the audio from the main speakers and to direct it to the headphone jack.
For either type I can see that it could ''possibly'' be causing the problem.
''The second possibility'' is that it is a faulty audio amp circuit in the TV although this doesn’t really explain satisfactorily why there is intermittent audio only in the headphones and not the main speakers as well.
Here are some poor images (apologies) taken from the service manual that show that the audio is fed out of the TV’s CPU to the audio amp and then to the speakers and that the headphones have their own amp.
[image|2151613]
[image|2151612]
(click on images to enlarge for better viewing)
Sorry to be so vague but the TV will have to be opened and the problem further diagnosed as to the cause. Hopefully it might be the headphone jack but if not then it is on the mainboard.
Note: The service manual can be used online. It is awkward however as you have to select the page number at the bottom below the document box every time that you wish to turn the page. To download it you need to register with the website.