Get the remote and press the menu button. Does the menu show or not. This tells us if it's the tower or the TV.
Docs found with https://www.google.com/search?q=40L1400UC&ie=utf-8&oe=utf-8#q=40L1400UC+menu+button
I got a secondhand Toshiba 40L1400UC that I just hooked up to my tower. The screen had randomly gone blank, but now after the logo fades out, the screen goes blank. I've looked all over the net but haven't found any feasible solutions. Any tips would be greatly appreciated. Thanks.

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