Bone stock daily driver, it was working fine till this morning.
Pulled all my fuses and checked all sensors.

Any tips and help on what else I could check to figure out why the temperature gauge is not working? Possible that the connections behind the cluster are bad??Or maybe bad cluster in general?

 

Check to make sure the signal wire didn't come unplugged, and make sure that wire isn't damaged. It should be a single wire, below your thermostat housing. There is a small pile of things it could be, but this is definitely the easiest to check.

 

 

The wiring/sensor could be the issue, but there are times when the Cluster itself fails. Not the likely cause but its worth checking if the other things check out fine.