Strange thing happened the other day - wondering if anyone else has had this... We all understand to not block the battery cooling air vents in the back seat - I've never really thought about it other than to make sure the vent holes are not blocked. The other morning I get into the prius to drive to work... there's nothing unusual - it's about 70' out, car is cool inside, battery is at all green minus one bar (usually how I leave it at night when I get home)... When I turn the car on, immediately a fan begins to blow at full force from the battery cooling area.. not a little, but A LOT... strange... we drive away and this doesnt stop. A few blocks away I stop, turn the car off and restart it... immediately the fan kicks in again... I stop again another block or two away and go through the manual but still I can't find anything other than the "dont block this vent" page. Figure there's not much I can do about this so I drive away and turn up the stereo... Hasn't happened before, hasnt happened since... had never heard that fan turn on, and it's LOUD... it was really blowing HARD... so... anyone else experienced this? very very odd
this happened to me once on my 2005 prius, it was weird because it was loud like a vacuum cleaner, since then it never happened
Now that you mention it, I don't think I've ever heard that fan turn on in my Prius. I usually have the auto AC set < 80ºC though.
I've had this experience once. If I remember correctly it was warm/hot out but nothing unusual. It was loud enough, I stopped to find out what it was. I seem to recall that it was on only a few minutes. This happened once in 57k miles. Ken
happens to me from time to time. when i drive off i tend to crack open the rear windows.. it increases the pressure of the cabin, forcing air through the battery vent.
The battery may be hot enough to trigger the fan. The time between the last last time you used the vehicle and the morning, may not have been long enough to cool the batteries enough. You said your battery pack is green when you start it up in the morning. Do you tend to have a lot of regen opportunity on the way to the garage (ie you live at the bottom of a hill)? When the car is shut off, the battery fan also shuts off, so there is no active cooling happening when you park your car for the night. I notice that in the summer, I'll occasionally have problems going into EV mode, in the morning, due to a toasty battery.
yes.. live ast bottom of a big hill so battery is usually completely full (80% of the time) or full minus one bar when I get home
:rapture:The fan will only come on long enough to cool the battery off and then it will turn its self off. Do not worry, Toyota has built a good car with it's own safety features.
Agreed. The op DID say their Prius is sometimes completely up in the green (which is appx 80% SOC) ... and battery charging, just like discharging, is the exact thing that generates excess battery heat, whether 70, or 95 degrees. So it's status quo. That said, I too haven't ever, since 2004, heard our Prius fan kick on. But being one of those in the high mileage seeker bunch, I work to avoid the green zone, by keeping the system in stealth while going down hills, if at all possible.
Maybe the battery fan is entering the self-maintenance mode and using the full-blast to clean the cruds in there....if any. Is it happening still and never stopped since?
Now that's a nice thought. Maybe the vents get dirty enough to turn the fan on? More likely any accumulated dirt is causing the heat to build up. Don't recall hearing this fan having kicked on with our '08 yet. It has been subjected to some hot and humid weather lately. Any one know what the temperature range is that turns this fan on? Is it the temperature of the battery, or a combination of the battery and it's location (lack of air circulation) that triggers the fan's operation? -Did I word that right?-
