Right away it sounds like a bad cap. You'll probably have to replace the power board or have it refurbished. It's common for those to have power/led combo boards and for 1 or 2 of the smaller caps on the led side to pop and leave the power side unaffected. It is also possible that it has a separate led driver and backlight inverter. In which case I'd look at those but it's been my experience that the ones with the led backlight boards separate from the power supply end up needing new led strips. This definitely sounds like a hardware issue and the back will have to be removed for troubleshooting.