Cooling Fan Starts in High Speed sometimes!

[texasv8]

The cooling fan starts in High Speed when i turn the truck on sometimes, being in the morning when i do a cold start or during the day.I can hear the fan running in High Speed from inside the truck for a short period of time then it goes back to running on normal speed.Is this normal?

 

[Big Bad Allis]

My new 2011 Yukon Denali and my 2006 Duramax LBZ does it too. I'll be curious to the answers that your thread gets. If just noticed in the Denali for the first time today.

 

[texasv8]

I tought the High Speed mode would come on only when the AC was running to keep the truck cool.But i tried turning the ac off, and it keeps running on HSpeed still.

 

[2007tahoe]

I tought the High Speed mode would come on only when the AC was running to keep the truck cool.But i tried turning the ac off, and it keeps running on HSpeed still.

I have never looked into the tahoe but I have played with a few lt1 camaros.
If the ac is cut on the high speed will come on but if you cut the air off the fan will stay on. If you crank the car with the ac off the fan will not be on. atleast that is the way a camaro is. The eng fan with the ac off will cut on for short periods of time to cool below a certain temp and then cut back off.

 

[eoncathell]

ohh.....that is the case probably!! even i face the came problem.......i always think that there might be some problem with ac and need to repair it....thanks for the solution!!!

 

[texasv8]

my ac is working fine.If there was a problem with the AC, it would do it all the time.I have a friend that works as a mech for a local GM dealership, i will call him and discuss this with him.

 

[stevek]

Don't fix it if it isn't broken.