Recently engine fans turned on after the engine is off, and after 2-4 minutes fans turned off.
The engine coolant temperature gauge shows normal temperature under all driving conditions.
The coolant reservoir shows an unusually high amount of coolant.

Any and all comments would be appreciated.

 

CHECK YOUR COOLANT LEVEL ! Wife's Equinox was doing this, and the coolant level was low ! A 50/50 mix Prestone GM Vehicles Dex Cool, or a General purpose Anti-freeze with the 50/50 mix will do.
Please check the level when the engine is cooled down.
This might help !

 

Sounds normal to me. Just be glad you have coolant which you can run past the "top" mark without harming anything.

 

Problem solved. Replaced the thermostat and replaced the coolant. In a kitchen pot tested the old thermostat by placing it in 195-degree water and it marginally/slightly opened.
Thank you for your replies.
9/9/23 Correction from the manufacturer temperature is 185/190 degrees.