bluetooth changes iphone volume when I exit my car

GrantdeC,

Thanks for the additional details. Here are some other steps that might help:

• Forget the car pairing with your iPhone: Settings > Bluetooth > 'i' icon next to your vehicle's name > Forget.
• Restart your iPhone
• Remove the software on the iPhone and add it back:

1. 1. Back up your iPhone: How to back up your iPhone, iPad, and iPod touch - Apple Support
   2. Restore the iPhone to factory settings using a computer: Restore your iPhone, iPad, or iPod to factory settings - Apple Support
   3. Set up the iPhone as new to test if the behavior still happens.

If it does happen when set up as new, reach out to the Apple Support team: Contact Apple Support

If it doesn't, try restoring your backup to see if it happens again: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Take care.

Hello GrantdeC,

Welcome to the Apple Support Communities, and I understand the volume will unexpectedly change to maximum when the iPhone disconnects from Bluetooth. I'll do what I can to help.

Here are some suggestions:

• Adjust the volume before connecting to the car's Bluetooth: Adjust the volume on iPhone
• Since it happens during Bluetooth connectivity, try the steps here: How to connect your iPhone, iPad, or iPod touch to your car

Enjoy.