I have a 2003 silveardo 4x4 longbed.

the check engine lights keep coming on everyday after i reset it. Its throwing a code saying the coolant temperature went to low? or something like that, It is really cold out but obviously should not be throwing that code. Any ideas how to fix it?

I was told the truck may of had a new radiator put in it, could it be a sensor that wasnt property put back on?