jaebi74,
Unfortunately, I'm not sure what happened, and I really can't be much help when it comes to service menu issues. I'm not quite sure what you mean by "it left IR after that 20 mins". Did you have some sort of image retention left on the screen?
I always recommend not going into the service menu unless you're an authorized technician.
--HDTech
i was checking the hours of usage of my pn50a450 through service menu for the first time. then somehow i made mistake to press ADC then HDMI calibration.
av components pc were success. but hdmi was like "wait" and then it made screen glows bright and dark back and forth. it kept doing it for more than 20 mins.
so i turned off the tv and turned it back on. nothing changed but my setting was reset. so i checked the service menu again and it was showing hdmi calibration was failed. right now i am using hdmi2 connected with pc. what should i do to make that hdmi calibration success? should i keep in on more than 20 mins? when i got into service menu my tv was reset it and left IR after that 20mins. i ran scroll and it almost got rid of it thogh. please help!!!

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