My tv just went off suddenly. for now it just shows a red light

It can be CPU or ROM failure. Most likely solution includes motherboard replacing, sometimes it's just reflashing enough.

@joshua41848 let us know what model your Hisense TV is and what you already checked. We also need to know if the power LED is blinking or if it is just on. For now, unplug everything that is plugged into your TV. Then unplug the TV. Now hold the power button depressed for about a minute. Connect one video source i.e. DVD/BR player etc. and plug the TV back in. try to power it on now.

Hisense TV's are known for bad backlights. We need to determine if your TV is really not displaying anything or if it is just impossible to see. A simple check for that would be to darken the room and turn the TV on. Then use a flashlight and angle the light at the screen on different areas. you might make out some shadows, your Splash screen or even see a slight grey color.

Let us know what you get.