Jvc lt-42xm48

[matthew_crane]

I have a JVC LT-42XM48 that will power on, but will not display any images on the screen(solid black screen). The backlights do light up, and if I change input to the tuner I can hear static out of the speakers. Channel/Volume seem to be functioning. I am not for sure what exactly is wrong, but I believe its something with the "Digital PWB" board. It seems like its not driving any signaling to the LCD.

I have attached pictures of the "Digital PWB" board.

Any assistance will be much appreciated.

[R_J]

Re: Jvc lt-42xm48

Check the voltage on the t-con board, could be an open FP1 fuse. should be 12 volts on the v12v test point

[matthew_crane]

Re: Jvc lt-42xm48

Ok, I checked the fuse fp1 on the T-con and seems to be good(.5 ohms resistance), where do i test for the 12v, at fp1? I have attached a picture of the t-con board.

[R_J]

Re: Jvc lt-42xm48

You can check for 12 volts on the fuse, there is a test point to the right of the fuse marked V12V . I usually check for signal on the lvds cable with a scope. but if you don't have one its hard to say if you have signal coming from the main board.

[matthew_crane]

Re: Jvc lt-42xm48

I checked the voltage right after the fuse and it is a very steady 12.01v. Unfortunately I do not have a scope to test with. Is there anything else I can check for?

[matthew_crane]

Re: Jvc lt-42xm48

Just for future reference, my issue turned out to be a faulty t-con board. I bought a replacement and swapped out the old board, and I now have a good clear image being displayed once again. I still have an issue with the hdmi ports not functioning, but I believe that is because of the stupid JVC "feature" that disables them when the back panel is removed. I just have to figure out how to enter "service mode" so I can re-enable them.