check the following. diagram and compare if it is that of your tv, the diode referred to in this diagram is d713 of 32v., on pin 4 there should be 18.5v with respect to hot ground, the voltage is lower than the zener voltage of the diode, So this diode is protective, if the diagram does not match look for the chassis or upload the components of the TV ... greetings.
sharp_27n-s100_7n-s180_cn27s10_cn27s14_cn27s18_chassis_sn-91_sm.pdf [6.20mb]