Another tip for fixing flat screen TV's that do not turn on is to check online and see if your model has information about forcing the set into service mode. While this does not help with finding power supply problems, it can be useful to spot backlight issues. Normally they will not turn on with a backlight problem and that can be confused as a power supply problem.
If it is a backlight problem and you force the set into service mode, the good LED strip will still come on and the screen will likely tell you what the problem is by displaying "Backlight Fault". Other faults can be detected and identified in this mode if the set will enter the service mode.
If it is a backlight problem and you force the set into service mode, the good LED strip will still come on and the screen will likely tell you what the problem is by displaying "Backlight Fault". Other faults can be detected and identified in this mode if the set will enter the service mode.