I am sorry, do you mean the temperature gauge on the dash is not working? If so the coolant temperature sender on the rear of the cylinder head feeds that signal to the computer.
From your description I would check the wiring at the sensor connection and back to the power train control module. The wires break right inside the connectors or in the wiring harness and you get no signal. If you have a scan tool put it on live data and watch the coolant temperature PID while you move the connector and wiring around. If it suddenly works you are near the problem.
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Wednesday, January 17th, 2018 AT 6:00 PM