Fans Running at Random times 6.2L/10spd

[jtav2002]

Has anyone had their fans run at random times? In the past couple weeks they will randomly come on when the truck isn't running hot. Had them run for a nearly 3 hour drive a couple weekends ago. Had them come on for short 10 minute drives. Once they come on they stay on until i turn the truck off (and then it runs for 10 seconds or so after). Keeps temperature  below the 160 minimum reading. Thoughts? 2019 AT4 6.2.

[BlancoSilverado]

Just curious, how do you know they were on for 3 hours during the drive?

 

[jtav2002]

I guess that’s a bit of an assumption on my part. I could hear it running anytime I’d stop and the temp stayed below 160 the whole time. 

[newdude]

Temp gauge won't read above 160?  Is the check engine light on?  Any stored codes anywhere?  

[BlancoSilverado]

1 hour ago, jtav2002 said:

I guess that’s a bit of an assumption on my part. I could hear it running anytime I’d stop and the temp stayed below 160 the whole time. 

Ok, i can barely hear mine thats why i was asking, 

NewDude's question is important, is there any lights on the dash. if not check for code, if still no codes i would take it in just to make sure. 

Maybe the sensor isnt hooked up/ wire is broken? 

Edited May 19, 2020 by BlancoSilverado

[davester]

Could they go on because you have the A/C on?

[jtav2002]

No AC on. No check engine lights. 
 

When the fan isn’t running temperature will snow normal. It’s just in the instances where it’s running it stays much cooler. 

[jtav2002]

Just to follow up. I had it in and they couldn’t replicate the issue. The following weekend I had the opposite issue almost with the temp randomly shooting up within seconds and then going back down when letting off throttle, accompanied by overheating message. After stopping and restarting fans ran for remainder of the drive, about an hour and a half with temp staying below minimum 160 reading. Took it back in again and it finally acted funny for hem but they weren’t sure exactly what was causing it. GMC told them to just replace the coolant sensor and all the associated wiring harness. No issues since.