Hi , I recently bought my 2013 prius but I have never noticed the hv battery fan working . when the car was in ready mode i opened the back door and put my ear on vent but nothing hear . I live in cold climate area is it because of that or the fan should work all the time ? never had a warning light .
The fan runs at whatever speed (from 0-6, iirc) necessary to maintain a safe battery temperature. In cool weather, I would not only not expect to hear it, but I would be concerned if I did. There are lots of OBDII dongles and phone apps you can get that will inexpensively monitor all sorts of stuff including fan speeds and battery temperatures if you're curious. Or just drive it hard with lots of hard acceleration and regenerative braking for 10 minutes or so to heat up the battery and then dangle some tissue paper in front of the vent to check for air flow. Or, just drive it. In the unlikely event that the fan isn't working, the car will tell you if the battery gets too warm. It will put a light on the dash and you can read the specific code with a code reader. But those are unusual circumstances. In your climate, the battery fan has the easiest job in the world.
I usually just reach back and put my hand next to the vent during hot weather to feel if the fan is on or not. Never been able to actually hear it when it does run...
I've heard it in the Gen 2 on really hot days, but just barely. I often hear the two fans on my Prime here in FL, but only when stopped and usually after extended EV driving. The fans are radial which makes them quieter than typical propeller fans.
i've never heard the fan in 15 years of driving prius, and not even with my new hearing aids. i did put a tissue on the grille in hot weather once to confirm it was working
Hybrid Assistant app has the best fan controller, but it's super slow to activate/latency... Dr. Prius App fan control is even more problematic... Most of all for every one OBD2 reader you can buy online that works, there's 5 that will be dead on arrival... Learn more here about difference between real and junk here: Hybrid battery diagnostic and repair tool for Toyota and Lexus
Turn the heater on, let the hv bat soak up the heat. It will spin up to speed 1 when bat is 96 F. 102 F is speed 2. Free test, not require to buy a obd2 Bluetooth thing
I've never heard the fan. I used to have a scangauge connected, occasionally monitoring fan speed, and saw it stepping through the various stages. But yeah, it would be reassuring to hear it. I believe if it's badly clogged and/or not working, there's a warning on the dash??
I purchased the Dr Prius app and it let's you adjust the temp that the fan comes on at , I heard and felt the fan running . Now that the car is turning 13 years old , I decided to check for dust build up on the fan , no filter ! The was the lightest coating of dust on the fan after 150,000 miles , I had to hear it run , thought that it never worked !
