Hello all,

I purchased a Sharp LC-42LE540U second hand but in good condition from the seller, and verified it was working in his lobby.
After getting home I plugged in a couple different HDMI devices (2 different Rokus) but there was no longer any audio from the speakers.

I'm thinking that during transport either something came loose, or a rain drop might have made it through the back cover on my trip to the car. (the TV was covered and it was raining very lightly)

I would like to open it up and make the repair but after looking at the data sheet, I am not sure where to start probing first. I have almost graduated as an Electronic tech, but have little hands on experience with TV repairs or their architecture

Michael

 

hi mcox,
This may help.
E

 

hi mcox,
This may help.
E

I have tried reinstalling the Televisions drivers, switching the HDMI cable, using an antenna as the source of video/audio, changing the audio output, still no luck.

Michael

 

FWIW, I had the opposite happen. A friend sent a failed HDTV to me for a last ditch attempt at repair. In fact she had already bought a replacement. I was all set to take it apart to look inside but had the foresight to test it first. It worked fine and I've been using it ever since. No idea what wiggled back into place.

Have you tried looking at the settings menu for the audio settings? I mean, you want to be sure the TV thinks the audio should be on and working. If the TV supports external audio, you might try that as well.

There are limited things to try but inside you will find a number of ribbon cables and connectors between the various modules. I'd try wiggling all of them, and disconnecting, inspecting all of them if the first round of wiggles doesn't do it. In particular you'll see wires from the little speakers coming back to the audio board. Obviously that's the place to start.

Another idea: Occasionally you can find a service manual for your TV or its related family members. These can have much more detail about troubleshooting. They're hard to find even if they exist, but it's definitely worth looking.

 

How to get the back off and check the connections., It's a 60in one , but it will be the same.

 

Okay Ive found some information and taken a photo. After checking this capacitors for shorts to ground, and making sure my chip has power. What would be your next course of action? Open question for anyone

 

Can you check if the digital audio output, or the headphone output works?

 

Can you check if the digital audio output, or the headphone output works?

I believe I tested the headphone output when I had it connected up, but I can verify that.

Id like to run the tests on the board while I've got it open though

 

There's a fuse at the audio amp. You should see 12V on both sides of the fuse and of course continuity if you can isolate it. Don't test for continuity in-circuit while it's powered up.

 

Have you got a known good substitute TV to try?
Good luck..............