LED backlighting issues on tv.

Hi. Yesterday my LED tv suddenly turned black while I was watching it. Thought it’s the electricity but later found out it’s not. Did some searching online found a tutorial that helps you diagnose a backlight problem. So now my question is, could it be possible for the backlights on my tv to fail even though they do switch on? When I switch on the tv they blink for about a split second then switch of. All of them! There’s 2 strips with 6 bulbs each , all 6 bulbs go on at the same time then shut of at the same time. Is that still a backlight issue on tv or is there something else?

NB: I don’t have a multimeter.