[Steve65]

Have 2020 3LT convert....today when went for drive the temperature gauge didn't move and when turned car off the fan stayed on a other 5 min. Any ideas

[OB0001]

check coolant level

[arpad_m]

Thermostat and/or temperature sensor, a relatively frequent failure. My conjecture is that the thermostat may have stuck open, the engine was never able to warm up with the cooling continuously on, and the (low) coolant temps you saw were correct.

The fan staying on for 5 minutes after shutting the car down is a failsafe: the ECM thinks the values it sees from the temperature sensor are unexpected or not realistic for some reason and tries to avoid the worst case scenario.

[MrCharlieV]

Thermostat. I had the same issue. 2016 V6.

[easttxss]

When the thermostat sticks open, even just a little bit, the engine doesn't warm up in the amount of time that the ECM is expecting. The ECM throws a code, the gauge goes to zero, and the fan is turned on high. This same scenario can happen with a bad coolant temp sensor (which was my case). Clearing the code will make the gauge and fan work correctly until the ECM sees the fault again.

[MyNameIs]

Originally Posted by Steve65

Have 2020 3LT convert....today when went for drive the temperature gauge didn't move and when turned car off the fan stayed on a other 5 min. Any ideas

Thermostat. Mine is a 17' SS, 68k miles. Same thing happened to me 2 months ago. Picked a Thermo. from the dealer and put it in in about an hour, problem solved. Dealer parts guy said recommended replacing every 3 to 5 years with average yearly driving so I got I got 7 years out of mine. The bad news for you though is I heard the V6 is more involved. I think the C6 V6 you have to remove the intake to get to the Thermo.