Hello, Lux197.
Welcome to Apple Support Communities.
I understand that you're having some issues with the Bluetooth audio and your car stereo. I'd like to help. Do you have other devices or other bluetooth accessories that you can connect with? This could help rule out some issues. If you believe the issue is with the signal, take a look through this article to see if any of it applies: Resolve Wi-Fi and Bluetooth issues caused by wireless interference
If you use a case, remove it and test. If you haven't done so already, restart your iPhone. Sometimes a restart can help resolve issues. You can also try connecting with a cable to see if that helps.
If these steps haven't resolved it, check for firmware updates on your car radio. These articles isn't your issue specifically, but the steps listed can help:
If your iPhone, iPad, or iPod doesn't connect to or work in your car
If you can't connect a Bluetooth accessory to your iPhone, iPad, or iPod touch
"If you still can't pair or connect your Bluetooth accessory
- If you previously connected your Bluetooth accessory to your iOS or iPadOS device, unpair the accessory, put it back in discovery mode, then try to pair and connect it again.
- If you can pair your accessory with some devices but not your iOS or iPadOS device, unpair the accessory from your other devices. Then try to pair with your iOS or iPadOS device again.
- Check with the accessory manufacturer to make sure that your accessory supports your iOS or iPadOS device".
Keep me updated.
Cheers!
