In case you want to try to pair the devices starting from the device into the car, note the car bluetooth's name is BMWXXXXX.

Pair with that device and enter the pin as 4 of those 5 digits (don't remember if the first 4 or the last ones).

After this initial pairing you'll be asked again for your own pin as usual (enter some 4 digits in one device, and re-enter them in the other one).

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