I just bought my new Prius C3 3 weeks ago. I noticed when I have my iphone 4s plugged in to the USB and my BT is on I don't get the notification noise that I always do when I get a text message. When I get a phone call it rings on the car speakers since I have it connected to my BT but not the text message. I commute to work over an hour each way and I hate to keep checking my phone to see if I got a text since it's not going off when I get a message. Does anyone have a clue?
Don't text a drive? My guess is that the phone itself doesn't make noise through its speakers when it's connected to BlueTooth, and the car itself doesn't do text notifications (as far as I know that's not an available feature), so there's nowhere for the sound to go. Just speculation, though. I might be full of it.
Unless you are in iPod or BT music mode, you won't get any notification sounds from your phone. Not ideal, as I don't get audio alerts from my main driving app, Escort Live!. You could try setting the audio output back to the iPhone after you pair and plug in the USB cable.
Only thing I can really think of make sure the phone is not muted because it will mute the sounds of the phone but not any sounds like music or video playback. I'm always on BT so it comes right through .