2004 pontiac montana

i have a 2004 montana and the gas gauge,speedometer,and the temp gauge all doesnt work properly what can be the problem

Did you check the fuse(es)?

Could you describe not working properly in a little more detail? Do they not do anything, do they move in unpredictable manners. do the work then not then work again?

I suspect a bad ground, a bad dash voltage regulator or ??? More info needed.