no picture back light is bliks once.

bala krishna  Since you have audio , you know that at least part of your main board still works. Now, in a darkened room turn the TV to a station where you have audio. Shine a flashlight at an angle against the screen. See if you can make things out like silhouettes, menus etc. If so, then you know it is your backlight (bad power board, bad backlight array). If you do not see anything then there could be an issue with the main board or the T-con board.

It’s a Philips TV so I am pretty convinced that this is caused by bad backlight strips.