On Tuesday, September 29, 2020 at 6:48:26 AM UTC-4, Stu jaxon wrote:
Hi Group, can someone help please? Im working on a Vizio led tv, D43-C1 Power Supply / LED Board 715g6973 p02-002-00h. when testing the output pins to main logic board with dmm, i get 5v on stby, 18v on 6 pins that the legend aks for 12v, when i disconnect the harness to the main board, i get zero volts on stby and 18v on the 12v pins.. when testin the k18a60v mosfet Q9102, on the drain pin I get 18v dc.. should i change the power supply board or the mosfet..?

The legends on Vizio boards often don't match reality. Also, are you sure you are using hot ground (PFC cap) when making your measurements on the MosFet?