Issue with tachometer

Hello all,

Just wanted to put something up in-case I might be missing something very easy or there may be a common issue.

I seem to be experiencing an issue with my tachometer when I rev the car it only moves the tachometer very slightly. are there any common issues that cause this or possibly any ideas where to start looking?

In addition to this, The AC display screen is also not working. The buttons work but the screen does not. I will attach some media for this issue.

https://photos.app.goo.gl/X2X5AdLLvTxgTocZ7 <— Video of Tachometer (Ignore the sound its really rough right now.)