I have a strange noise coming from behind the passenger dash when I turn on the radio. The noise is a fan-like whirring sound, it is not any type of static sound or some sort of short from a bad speaker. It begins a half-second or so after turning on the radio and stays on for a second or so after.

Any ideas?

 

As the radio is warming up, it probably is able to pick up on the US spy satellites keeping an eye on you. . .or aliens living in your neighbors skin communicating via an open channel to the mother ship

Just my 2 cents

 

capacitor on the side of the coil is a good place to start.

 

It may be the cooling fan kicking in so as to be ready when you "jack up the volume".

 

or the disk spinning ?

 

i like the disk spinning idea.

is it aftermarket or stock? do you think its coming from the radio or more from the passenger side dash? what if you stick your head up by the glove compartment and turn it on, where do you hear it?

 

I hear a whirring sound whenever I turn my cd player on.. it's my amp under the seat (aftermarket). Is it possible you have a factory installed amp that has a cooling fan? Just a thought.

 

wouldent you hear a cooling fan the whole time? with the volume down...

 

He didn't specify whether or not the volume is up or down.. just turning it on.

 

not always all the time. usually when you turn on a PC (and i assume an amp is the same) it runs the fan a few seconds just to be safe until it can determine the actual temp.

 

My amp runs from the point I turn my cd player on. If it's powered off, the amp shuts off as well. I don't think it's quite as complicated as a PC.. but maybe some crazy high-end ones are..

 

could be aliens.