Testing AC Plug

If you are a new technician probably you must note this about how to test a plug of a tv,radio, computer and so on. We usually test a plug by its resistance or continuity if it is open or not and if we see some reading in our tester, digital multimeter or analog tester we presume it is okay. We must sure that the reading in our tester when we measure the resistance or continuity of a plug must be in 000 if it is digital tester and if it is analog be sure the pointer of your analog meter deflect up to zero because i have encounter one plug, the otherside is deflect up to zero but the otherside of the plug have a reading of hundreds and i presume it is okay because i am new technician on that time and this tv has no power. So when i plug the tv and test the power supply it has no power. I start to test the input supply of ac(alternating current) from the outlet on the plug and i measured zero volt. I found out that only few of wire strands are connected that's why there is no power coming on the plug of a tv. So be sure when you test a plug of a consumer appliances and it has no power coming in comply to the above mentioned  and if it's okay test the fuse and other components on the power supply.