Some systems have the fans kick up to a higher speed or extra fans turn on automatically when the a/c is engaged and some systems only add extra fan speed or engage a second cooling fan when the engine reaches a certain temperature. In any case, it's a normal condition unless the noise is excessive and may be a problem with bad bearings in the fan motor if it's too noisy. Have a local shop or dealer check it out to see if there is a problem but it sounds like normal operation.
The fan is coming on because your increasing the amount of heat your car rad needs to get rid off. Rad fans used to run the whole time the car was running. They were attached to everything else through fan belts. in newer cars the rad fan runs off a thermostat in your rad. When you turn on the AC your rad now needs to get rid of the heat from the cab of your car as well. Also when your driving down the highway your fan will probably be off. This is because the air is naturally flowing through your rad. When you stop at a light the temps will go up and bring your fan on. Once you start driving again the fan goes off.
It's perfectly normal for the electric radiator cooling fans to spin fast when the air conditioner is on which pulls heat through the radiator and *air conditioner condenser.
Year, make, model, engine. They're not all wired the same.
my car runs smoothly, but when i turn on the AC, in about 5 min. the radiator electric fan turns on fast.
fast enough to hear it all the time you are driving it. when i turn off the AC 5min in the noise disappears!!
can someone help me please its driving me insane.
