I have a 2006 xB, automatic, with 1800 miles on it. It has developed a high pitch noise, like a tv running with the volume turned off or a light turned down on a dimmer, from under the passenger side of the dash. The noise starts within 2 minutes of a cold-start and you can also hear it with the motor not running, but with the ignition key on once the car has been running. The dealer said "could not duplicate," but did admit that it was hard for the techs. to hear high pitch noises. Friends can hear it, as passengers, so I'm not alone! It is not intermittant - it's any time the car is "on." Any ideas?

 

Do you have the fan on? That's where it is located...

Also try changing all the heat and A/C controls and see if the sound changes. (I once had a Plymouth with a slight irregularity in the A/C plumbing that would make a little high-pitched noise whenever the A/C was on...)

Good luck!

 

I've tried shutting off the fan and radio and have tried turning on and off the a/c, rear defrost, flashers, etc. to see if that would have any impact - they didn't. It looks like there might be some sort of metal box under the glove box that might be the source. I was thinking maybe a faulty relay or resistor, etc. Thanks for the input.