I created your own post since the previous thread was a little different than your question.
At this time, all Pandora automotive implementations require you to use a compatible iPhone or Android with an active internet connection in order to stream music in the car.*
Since instructions for connecting devices to your car may differ. I recommend referencing your car's manual for the steps to connect the car system to your phone. Using the Voice Commands for your unit (if available) is often the easiest way to do this.
Thanks for posting to community
*Use your mobile device only when conditions allow and as permitted by applicable law.