Was a bit of a hot day today and my black Prius had been parked in the sun all day. When I came to drive the car the a/c came on full power to lower the cabin temperature.

However, from the front of the car the two fans were making a really weird buzzing, humming noise (but were both spinning at high speed). Now I know a/c fans work flat out sometimes but I have never heard a noise like this before on a cars a/c. It almost sounded like the noise a jammed lawnmower makes, or some of the old lift doors make. Almost an electrical buzzing noise of a solanoid but it was coming from the two fans.

Is this normal? Was it the fans or maybe the compressor or both? Has anyone else experienced this or similar? The a/c was working fine and was ice cold. When the cabin temperature reduced the noise reduced a disappeared with it. However, I did manage to repeat it by turning the a/c internal fan speed to full on a low temp setting.

Should I be concerned? Is this normal Prius behaviour or should I be visiting my dealers in the next day or so?

Appreciate any advice

p.s. It wouldn't be the inverter coolant pump for the battery as it was hot inside the car?

I have had Gen II and have a GEN III now and have not ever had this sort of noise.

Sounds like an unhappy electric motor in the fans. Suggest a trip to Mr T sooner rather than later!

Trafficman

My air con motors were noisy yesterday - I just put it down to running at full power when just turned on with a high external temperature. Everything back to normal once the cabin temp was down.
Aren't these driven by electric motors rather than the usual aux belt, so could expect a hover mower noise?

Yes, the air con is electrically driven. This allows the air con to run in traffic when the petrol engine is off and also the pre-air conditioning you can get with the solar roof and plug in examples.

Just been to the dealers this aft to book my 20k service and asked them to double check the a/c. Apparantly all normal and ok, despite being noisy at full welly.

[quote name='Grumpy Cabbie' date='24 May 2010 - 05:14 PM' timestamp='1274717664' post='1004735']
Just been to the dealers this aft to book my 20k service and asked them to double check the a/c. Apparantly all normal and ok, despite being noisy at full welly.
[/quote]
The Prius is like that. Gen II was the same. The Gen II handbook warned you not to worry about wierd noises from under the bonnet and explained that it was perfectly normal. Gen III is the same, but I haven't noticed the warning.

So much for silent electric cars!