I have a 2010 Ford Fusion Hybrid and it has the same same high pitch whistle... it sounds like a dog whistle. Seems to be electrical. They already replaced the blower motor which ofcourse didn't fix it. They then replaced the cabin filters and told me that replacing those fixed the noise. Which ofcourse it didn't. Basically, when you put the defrost or heat power on more than 3 its horrible. the next to highest level is the worst. Seems to get worse when the driver's side heated seat is on. But it's steady. Doesn't fluctate. Constant and horribly annoying. The Ford dealer here has had my car 4 or 5 separate times for this. Now I've had a loaner for 3 days and they still have no idea what that problem is. After they replaced the blower motor and cabin filters I had the manager and the tech sit in it, they said...O that noise...that's not the blower. They never even bothered to listen for the noise... as soon as I mentioned it was a heating/defrosting issue they just replaced the blower and hoped for the best. I'm very frustrated. Anyone that can help with this, your input are greatly appreciated. Thank you!!
