Alternator whine

My 2002 Buick Rendezvous has started making a high pitch whining noise that has been getting louder the past few weeks. Depressing the accelerator makes the noise higher pitched. My mechanic said that it is alternator whine coming through the stereo speakers, whether or not the radio is on, and the only way to get rid of the noise is an expensive re-wiring of the speakers. But, if I can live with the noise, there’s no problem. Any advice on how to get rid of the noise inexpensively?

Check the alternator output … one of the main diodes may be blown resulting in a high pitched whine and a decreased battery charge current.

I think you need a new mechanic. The alternator can’t make noise through the speakers is the stereo if off.

Where are you hearing this noise? Is it inside the car or coming from under the hood? Either way, I suggest you have the alternator tested at an auto parts store or by another mechanic.

This sounds really BOGUS to me.

I just checked, and the noise is coming through the speakers in the front doors. In my garage, I started the car, turned off the radio, got out, and put my ear up to the speaker, and sure enough, the alternator whining is coming from the speaker, with the radio off. Sounds strange to me, but it was unmistakably coming from the speaker.