I am lucky my SO (more on that in FHOP) had the diagnostic tool to see why my Prius woke up with a headache as I was starting my day. Displaying the orange triangle, telling me to park and then telling me to shift to park... Yet I parked her in the garage the night before. I should have had a pen at the ready as I did not get the three codes that came up (they are stored on my SO's work computer now). Two were about some miscommunication - one having to do with navigation; the third was a malfunction with the USB port... I have had a few issues with connecting my iPad to the USB port. I am getting close to 10K as well. Very fortunate to have a Prius doc in my world!
Please update us on the code. It is interesting that the Prius will trip a light for an accessory too. I always thought it is reserved for a malfunction in the vehicle core.
Glad to hear you are doing well with SO! The message about Shift to Park usually means that you have a door that is not fully closed. The codes about the nav units and USB ports are not the codes that triggered the orange triangle. These are only codes that you can typically read in the Diagnostic Mode and have to do with the audio system, Nav unit, etc. You can ignore these codes.