Nothing you described as " working " has anything at all to do with the "phone as a key" function. Blutooth music, phones, etc, showing connected, has nothing to do with setting up the phone as a key.
The phone has to be paired specifically as a key, which is a separate process to pairing it for bluetooth music etc.
If your phone is already paired as a key, remove it and pair it again. If it isnt, go through the process to pair it. Relevant info in the tesla online model 3 manual below (both link, and relevant text).
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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).