306 gti degree indicator malfunction

I have a 99 model 306 gti car one day when I got into the car and started it, I realized that there were 3 lines instead of numbers in the deree indicator in the center console.

I can't see any comments for this malfunction, I have to see, I don't understand the event because I can help if you are in Istanbul ...

degree sensor is broken

malfunction or electrical failure

The construction gets better ...

Who is the person of this or where exactly or who knows the sensor, I am a victim of it.