2009 Aveo, At what temperature should the radiator fan turn on ?

2009 Aveo, At what temperature should the radiator fan turn on ?

The gauge needle/pointer does not go above the center line, car has 95K miles and thermostat replaced 400 miles ago.

The system was purged by taking the cap off the coolant tank several times after the engine warned up and filling it as needed.

Is there a known relay or sensor controlling the fan that has issues ?

If you know the actual temperature at which your fan turns on, I can check mine out.