TV is on with cable but screen is black I can only hear sound

georgettesorrell in a darkened room and with your TV on a channel where you have audio, shine a flashlight at an angle against the screen. See if you can make out shapes/silhouettes. If so, it is your backlight array that has failed. If not then it is possible that this is a power board or a main board issue. For that you will have to remove the back off your TV and take a look at the boards. See if there are any burned/missing or otherwise "off" components. Next you would have to measure the voltage coming from your power board and going to your main board.. There should be something called BKL ON etc. Let us know what that voltage is. Post some good pictures of your boards with your QUESTION. Also, we need to know the exact model for your TV .

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