Leave an old or cheapie HF OBD11 reader in the car to check those surprise codes that occur when far from home. And a cheat sheet of the Code definitions.
In future I think we'll all be using something like this:
https://www.amazon.com/dp/B00652G4TS/_encoding=UTF8?coliid=I3OI0C4YAYGKPF&colid=1J8X1XZSYY0W7