With the set unplugged, remove the back cover. First stop is the power supply.
First, check the line fuse. If it is wrapped in white tape, you may have to use the back-to-front feature of a multimeter to check, or just replace it. After that, check the fuse above the transformer on the Hot side of the board. Next, check for domed, leaking or bulging capacitors that may need replacement. No indicator makes me look at the power supply first.