I was driving today with no music on and noticed something strange. I heard something "roasting" in the backseat...and looks like the noise comes from the battery vents. It sounds more like "roasting" noise than fan noise. Do you know if the battery was overheating? The weather was 90 degrees (feels like 96) and I had the AC on ECO at Speed 1 (78 degree setting).
Although it hasn't happen to me, I suspect that is your HV battery fan running. Is it constant? Do you have a level drive or a lot of hills? In anycase, if there are any real problems, you would likely get a warning light on the dash. p.s. when hot outside, keep your AC running as that assists cooling of the battery.
I only hear why accelerating. As soon as I take my foot off the accelerator, the noise stops. I only heard it today (had the music turned off) and on a flat road. I thought the HV battery was passively cooled. It could be that the battery is discharging and produces noise...but it is loud.
This thread was started a few days ago about the same thing. http://priuschat.com/forums/gen-iii...n-does-your-hybrid-battery-pack-fan-turn.html
By roasting sound do you mean a popping sound like hot grease? If there is some kind of discharge happening that you can hear I would guess there is a serious problem. If it is reproducible, I would go straight to the dealer.
i'm not sure what a roasting sound would be. ive heard fan sounds sometimes, its normal. if you hear a whirring sound, i've had that on my old cars when im accelerating with the radio on but nothing playing through the aux jack.
Agree with the other posts that "roasting" might not be the best description of the sound, but my battery fan is noticible and definitely runs faster with more throttle too. I never heard a battery fan sound in my old 2004 Gen II, but I hear it often in my 2010 Gen III.
I've experienced the same thing. It is perfectly normal & yes the fan goes faster with speed of the vehicle. The first time I heard it, I thought one of the rear windows was not fully closed because it sounded like air rushing through an open window!
