2016 Yukon Denali radiator cooling fan runs after engine shut off.

[cleancut41]

The radiator cooling fan on my 2016 GMC Yukon Denali, 117,000, runs on high after start and continues to run for a couple minutes after engine is shut off. This hasn't happened before. The temp gage stayed on zero (160) after a 10 mile drive. No warning lights except oil change reminder, and it is due for that. Any ideas?
Update: On my way home, the temp gage moved to about 190. When I shut the vehicle off the fan stopped as is normal.

 

[sealandsky]

I have found that the cooling fan runs when it wants to, no rhyme or reason...

 

[91RS]

Thermostat. P0128 will be stored in the ECM.

 

[xmms]

Did you do anything to fix this? I came here to post the same exact issue with a 2018 Yukon with 114k on it.

 

[2001 TX Tahoe]

I had the same issue and it was my thermostat.

 

[xmms]

I ran the heat and the thermostat seemed to right itself…for now. But sounds like my next step is is replacing it.