Hi everyone. [Sorry for the long, detailed post in advance].
I have a Sharp LC-52E77UN which randomly shuts down--could be within 15 minutes, could be 40 minutes, over 1 hour, it's unpredictable. From reading the service manual, I was able to get into service mode (where the K is displayed), and found the following error flag toggled: "04 Initial Communication Error 4 -- Error reason: To the communication setting reception," which, from contacting an eBay TV repair store, I was told is caused NOT by a bad TCON (which was my first guess), but rather the motherboard....
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