Hi Michael,
You haven't given us much to go on. Have you done any troubleshooting or measured voltages?
Let's start with the power supply. At connector CN3 you must have:
PIN 13 : 3.4V Standby at all times the tv is plugged in.
PIN 11 : Approx 2.5V PWR-ON when you attempt to switch the tv on. This is supplied by the main board to turn the bulk of the PSU voltages on.
PIN 10 : Approx 3V AC-OF DET. This should appear when the PSU fires on. If it is missing, the tv will not power up.
See how you go with these for starters. If the 3.4V Standby is zero, check 10 ohm fusible R6200 (usually white). Make sure you discharge the main ripple filter
(the large 450V one) first, or you might end up with a duff meter as well.
If R6200 is indeed o/c, you'll find that the 5V switching IC IC6200 (MIP2H2) is gone as well.
Bruce