Still figuring my way around the audio system in this car... On my other Toyota/Lexus, when the phone was connected to the car via Bluetooth the volume on the phone itself continued to work. For example, if I wanted to quickly use Google maps on the phone, it would still read out the directions from the phone. Not so on the Prime with 11.6 screen. Once connected to Bluetooth, the external speaker no longer works on the phone. So if I want to hear directions from the phone itself, I'm out of luck. Is there a switch/option within the phone or audio system to allow this functionality to continue?
If Bluetooth is working, you hear the sounds from the car speakers, don't you? So, why do you want the phone speaker to make sounds? I don't think I had any car that Bluetooth paired phone made sounds while paired to the car.
When using an external BT speaker like the car, make sure your "Media Volume" on your phone it turned up to max. My Samsung S20+ like to "protect" the user and will turn the volume back to 50% after a day or two. The "Media Volume" is the sound level being sent to the car, Google Maps, or FuGoo, ear buds, or whatever. Set it to max and the control the volume via the car.
If I'm listening to FM or Sat, there's is no sound coming through the speakers from the phone if I'm using the phone independently for directions for example. And the speaker on phone appears disabled. The only way to hear the directions through the speakers is to select "Bluetooth" as the source from the Big Screen. But then that disables sound from FM/XM of course as it's now playing the Google Maps directions through the car speakers. This is the only car I've had where you can't use the phone speaker independently once paired. That is to say, a paired phone uses the car speakers for Calls, Messages and Music. Everything else still played through the phone speaker (Directions, OK Google, etc) Quite bizarre. Also works the same way on wife's Audi...phone speaker can be used independent.
OK, I see now why you want to hear the sound from the phone. You are saying once your phone is paired to your car even if the Bluetooth is not used for audio (music), your phone speaker is completely disabled. I don't know what phone you are using, but my Pixel XL (Android phone) whiled paired to my car, still makes the sound through the phone speaker. I recently had to use Google Maps when ScoutGPS stopped working. The phone was still paired to the car, but the sound was coming from the phone. At least on my 2020 Prius Prime LE with a smaller 7" display, the phone speakers work even if it is paired to the car. Come to think of it, with my previous 2017 Prius Premium with a larger 11.6" display also worked the same way. I could hear the phone sound from the phone if Bluetooth is not selected as an audio source, while the phone was still paired.
There is call pairing and media pairing. In a Lexus it connects with both options so yes it does "smartly" use the phone audio when not paired and active as a media device. But when someone phones or you get a text message, it plays through the car speaker. When you switch to Bluetooth Audio, all sounds go through the car and nothing through the phone. In all the Toyota's I've seen there is no distinction. It is just bluetooth pairing, all or nothing. So all sounds, whether Bluetooth Audio is active or not, are routed to the car. You can disable this on the phone by deselecting media pairing but that is deselected forever. Then you have to reselect it. In my cars, it is bluetooth audio all the time. The phone is the master. It works on all vehicles all the time and if I am in the car with tunes, I have my phone on me or at least within a few meters of me. Never leave without it!
This is the same problem I'm having. I have a '21 PP I'm using Samsung s21+. I'll follow this post. Thanks
On my Prime, while I can hear phone calls through the car speakers using Bluetooth, I can't hear directions from Google maps. What works is while the voice from the directions is speaking, you need to turn up the sound volume in the phone. Then you can hear the voice directions from the phone speakers. You can't change the voice volume unless there's a voice speaking, so you have to be fast to get to the volume buttons. I have no idea why it's this way.