Hi @cyclist2000! Thanks for posting and sorry for any confusion.
At this time, Pandora automotive implementations require you to use a compatible Android or iPhone with an active internet connection in order to stream music in the car.
Unfortunately, Offline Mode is not available through Android Auto or CarPlay. However, there is a feature request for this idea in Pandora Features. If you'd like to see this idea for Android Auto, I would recommend giving the idea a vote. You can check out the request here: Offline Option for CarPlay/ Android Auto
In the meantime, if you'd like to use Offline Mode, I suggest connecting to your vehicle via bluetooth only.
Hope this helps. Sorry for any disappointment.
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