I had the same problem with my new TH-50PX60B. I turned the tele on then after 5seconds it would switch off. The standby light would then blink on and off 11 times, pause for a second then flash 11 times. This would continue until the power wasturned off. Note the TV would not turn on for more than 5 seconds.
I solved this problem by turning the tele on and checking the fans at the back. My tele had 3 fans. If one of the fans is not turning, this will be the cause of the problem and the tele will shut down under the Emergency Shutdown System. To clear the fan try blowing on it to free up any dust etc. If that still doesn't work try using a thin instrument (tie wrap etc) to manually turn the fan and free it. Then power off the tele and turn it back on. The tv should work perfectly.
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