Cooling fans on high at cold startup.

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06 Escalade. Recently the radiator cooling fans have been coming on at cold startup in the morning. Like the engine is really hot, the fans are going fast. You can hear it as I leave the garage. Is this normal? I don't remember ever hearing this before at startup
 
Did you leave the AC on when you shut the engine off? Many vehicles are programmed to run the cooling fans when the AC is turned on.
 
Company truck I got now. A 2004 Ford F150 does this. Annoying. The garage said it's normal. If it's normal, I can't imagine anyone ever buying this truck. Goes away after it warms up and doesn't do it on warm starts.
 
Originally Posted By: Panzerman
Company truck I got now. A 2004 Ford F150 does this. Annoying. The garage said it's normal. If it's normal, I can't imagine anyone ever buying this truck. Goes away after it warms up and doesn't do it on warm starts.

Probably a mechanical fan. At least, my friends '05 was mechanical and yeah those will run when they are cold simply due to the viscous clutch being cold. This has always been a thing with these clutches going back decades.. When it warms a bit from friction it will unlock.
The running when cold is a good thing because it tells you its still working properly. Unlike the one on my friends truck that was always quiet and let the engine overheat while it was idling.

As for the escalade, yeah, if you have the A/C on the fans will come on as soon as the engine starts. If you shut the a/c off, they should then shut off. If they don,t then I would say that is abnormal behavior; perhaps a stuck relay or something.
Something I just thought of; if it has PWM variable fans, the controller for the fans could be bad and instead of varying the fans the FET or other component internally is shorted so the fans always run 100%. Something to check.
 
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Going to make sure the AC is off before it's shut down for the night. Check it again tomorrow morning
 
Originally Posted By: LeakySeals
Going to make sure the AC is off before it's shut down for the night. Check it again tomorrow morning


That's my bet. Let us know.
 
My Accord used to do that. It was a bad cooling fan switch. I replaced it and now the fans come on only when they're supposed to (when the engine starts to get too hot, and/or when the AC is on). Then the junk aftermarket switch broke after only 2 years or so and I had the same symptoms again. Replaced it again with a Honda OEM switch, and it's been working properly ever since.
 
If a fault is detected in the circuit to the temp probe the default is fans on high all the time. Normally a CEL is set if this is the case.

Also if the engine fails to warm up in a few minutes [bad thermostat], the fans will again go to high speed as the computer thinks the indication may be faulty. This seems unrelated to this case.
 
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