sony kdl-40ex400

hi i have been tinkering with this tv i got..no power 100% dead no lights on front nothing.all caps good and all fuses good
have done some research.took tv aparti do have 3.3v standby voltage from power supply but standbylight not on.'but no other voltages...anywhere

i then ndisconnected the cable to main board and jumpered the 3.3v standby pin to the power on pin on main board end of cable..and i get no voltages anywhere on the power supply board other than the 3.3 standby volatage and obviously 3.3 pwr on volatage

so my question is that if i do have 3.3 standby voltage why do i not get a standbylight???....and i originally thought it was a mainboard issue since soemone said if you get standby voltages but no standby liught ...the main board is the problem and the power supply is good.....well im not sure about that in my case since i have no volatges on power supply other than 3.3 standby

any ideas whats going on here?

thank you