Hey all.

 

I've had this recent problem of a high-pitched humming coming from under the hood after I shut off my 02 obw. It tends to happen 1-2 seconds AFTER I turn off the key and lasts for about 2-3 seconds. It sounds like the hum is coming from somewhere near the right front wheel. I've also noticed it happening a little as I'm idling at a stop with the A/C on. Yesterday, it seemed as though it was giving out a little hum as the A/C compressor cycles off. Any ideas? I sure hope my compressor isn't going! I only have 40K mi on it.

The only thing that comes to mind is possibly cooling fan(s)?

Yeah, I was thinking fans as soon as I read the subject...they randomly go on (alot) when the AC is on.

I had the same problem with my 02 outback . In my situation It started out as a low hum same as yours . It got progressivly worst to were whenever I accelerated I would get this fog hornlike sound from the ac . Took it to the dealer and he ordered a new expansion valve for the ac . My ac is now so much better then before . Hope this helps .

 

Mike in South Jersey

I had this same problem with my 01 legacy. i had the car for 3 months and the a/c would make a resonating noise when i shut off the car. looking at my service record, there was an o-ring repair (code 015071 if that helps at all...). the repair was no charge under warranty at 6000 mi.