I bet that diode shorted. Many times these fail in LCD power supplies and are easy to ID. Lify one leg from board and take continuity tester (ohms prefered) and test continuity. You'll have an open one direction and will show a "short" in the other direction, just flop the probes. If its shorted both directions, replace. Transistor can be tested
https://vetco.net/blog/test-a-transistor-with-a-multimeter/2017-05-04-12-25-37-07#:~:text=Hook the positive lead from,OL” (Over Limit).
