Why does my backlights come and fade out to dark on my Vizio E320-B2.

I connect my tv to power and the led strips come on (dim) ,then they slowly fade away to darkness,I replaced the power supply and seems I have 9v at standby pin and hardly any voltage going to the backlight,I’m grounding the multimeter to the case,any help would be greatly appreciated…. Thanks

. Here are some pictures, I unplugged the main board and the led strips didn’t come on at all , I have 5v at the standby pins and hardly any voltage at led+ pin connector….any help would be greatly appreciated….. thanks

. I hope these help,let me know what else I need to provide you with….Thanks