Playing music has nothing to do with being connected to the car as a phone key. There are two different pairing actions that need to take place, one for the phone to play music, and a different separate workflow to pair the phone as a key.
Go back through the workflow and pair it as a key. Here is the tesla online manual, with a paste of the relevant section:
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Learn about the types of keys that your vehicle uses to lock, unlock and drive.
www.tesla.com
Phone Key
Using your phone as a key is a convenient way to access your Model 3. As you approach, your phone's Bluetooth signal is detected and doors unlock when you press a door handle. Likewise, when you exit and walk away with the phone key, doors automatically lock (provided the Walk-Away Door Lock feature is turned on; see
Walk-Away Door Lock).
Before you can use a phone to access Model 3, follow these steps to authenticate it:
- Download the Tesla mobile app to your phone.
- Log into the Tesla mobile app using your Tesla account user name and password.
Note
You must remain logged in to your Tesla account to use your phone to access Model 3.
- Ensure that your phone's Bluetooth settings are turned on. Also ensure that Bluetooth is turned on within your phone's global settings for the Tesla mobile app. For example, on your phone, navigate to Settings, choose the Tesla mobile app, and ensure the Bluetooth setting is enabled.
Note
Model 3 communicates with your phone using Bluetooth. Keep in mind that your phone must have enough battery power to run Bluetooth and that many phones disable Bluetooth when the battery is low.
- Ensure access to your location is enabled by viewing the Tesla mobile app in your phone's settings and selecting Location > Always. For the best experience, keep the mobile app running in the background.
- On the touchscreen, ensure that Allow Mobile Access is enabled (Controls > Safety > Allow Mobile Access).
- While inside Model 3 with a key card handy, open the Tesla mobile app and follow the prompts to set up a phone key.
To view a list of keys that can currently access Model 3, or to remove a phone key, touch Controls > Locks (see
Managing Keys).
Model 3 can connect to three phone keys simultaneously. Therefore, if more than three phone keys are detected and you want to authenticate or pair a different phone, move the other connected phone key(s) out of range or turn off its Bluetooth setting.
Note
If multiple vehicles are linked to your Tesla account, you must ensure that the vehicle you want the mobile app to access is currently selected on the mobile app.
Once a phone has been authenticated, it no longer requires an internet connection to be used as a phone key for Model 3. However, to use the phone hands-free, access your phone's contacts, play media from it, etc., you must also pair it and connect it as a Bluetooth device (see
Pairing a Bluetooth Phone).
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(managing keys link above)
To display a list of all keys (phone keys, key cards, and key fobs) that can access your Model 3, touch Controls > Locks. An icon displays next to each key to indicate whether the key is a phone key, key card, or key fob. Use this list to manage keys that have access to your Model 3. To add or delete keys, see
Adding and Removing Keys.
Model 3 supports up to 19 keys. When you reach this limit, you must delete a key before adding a new one.
Note
You can use the same key for more than one Model 3. This prevents you from having to deal with multiple keys when you switch vehicles. If you customize the name of an authenticated key card or key fob on one Model 3 (by touching the pencil icon), any other Model 3 to which the key card or key fob is authenticated also displays the changed name.
Adding and Removing Keys
To add a new key card or key fob:
Note
When adding a key fob, ensure it is at room temperature. Pairing a key fob that is very cold can be unsuccessful.
- On the touchscreen, touch Controls > Locks then touch + in the Keys section.
- Scan your new key card or key fob on the card reader located behind the cup holders on the top of the center console. After the new key card or key fob is recognized, remove it from the card reader.
- Scan a key card or key fob that has already been paired to the vehicle to confirm new key pairing.
- When complete, the key list includes the new key. Touch the associated pencil icon to customize the name of the key.
To add a new phone key:
Note
You must enable Bluetooth on the phone and have the Tesla mobile app installed and connected to your Tesla account.
- While sitting in Model 3, open the Tesla mobile app (if you have multiple Tesla vehicles, select the appropriate vehicle), then touch Phone Key > Start.
- Scan an authenticated key card or key fob on the card reader located behind the cup holders on the top of the center console (see Key Card).
- When the mobile app notifies you that pairing was successful, touch Done. The key list on the touchscreen (touch Controls > Locks) includes the newly authenticated phone key. The name of the phone key is determined by the name used in the phone’s settings.
Removing a key:
When you no longer want a key to access Model 3 (for example, you lost your phone or key card, etc.), follow these steps to remove it.
- On the touchscreen, touch Controls > Locks.
- In the key list, find the key that you would like to delete and touch its associated trash icon.
- When prompted, scan an authenticated key card or key fob on the card reader to confirm the deletion. When complete, the key list no longer includes the deleted key.
Note
Model 3 requires at least one authenticated key card or key fob at all times. If only one key card remains on the key list, you cannot delete it.