I'm working on a 2016 2.7 ecoboost, the temp gauge is pegged on high all the time fans are on and has a miss. Haven't had a chance to stick a scanner on it yet just looking to see if anyone has had the same problem. To me seems like the wires from the sender have to be grounding/shorting? Any ideas?

 

You might consider unplugging the connection from the coolant temp sensor and see if any change. If no change , then suspect a possible wiring problem.
It is a bit of work to open the dash and unplug the signal wire from the gauge, but that could help eliminate the gauge and sending unit, leaving a definite wiring problem.