When the YELLOW light to the left of the SONY logo stays on when the TV is turned on, the only way to turn it off is go into Settings, Device Preferences, Date and Time, and then turn "Use 24-hour format" off/on and then back on/off. That will turn off the yellow light - for THIS use of the TV. However, when the TV is turned on again next time, the yellow light is on again. So, that process must be followed every single time. I recommend calling Sony Support and logging this issue, as they don't seem to feel it IS an issue as there aren't very many reports about it.