Facing TV Problems? Ask a TV Technician.
Hello, First- sorry you're having problems.
Secondly, no there is no reset button inside of the TV.
Additionally, these symptoms points to a failed Mainboard- which is the board you see with all of the AV Input jacks on it, and when the set stays locked with the LG welcome screen and no response form any of the remote commands, TV buttons, and no AV processing- it means your Mainboard's EEPROM (processor) has failed. This requires REPLACEMENT of the Mainboard in the TV to fix the issue.
Since you have the back of the TV off, I am assuming that you are looking to repair the set yourself, Yes?
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