Sorry, I forgot to mention that I was going about 30MPH downhill when the diagnostic appeared. There was also a fast bing-bing-bing sound, then the diag went away. I will do an OBD dump tomorrow and report.
I ordered a charge hood made of clear plastic and removed the rubber magnets - they were weak.
I slid in five epoxy coated 60x10x5 neodymium magnets into the pocket where the rubber magnets were held.
Then I glued a thin strip of steel behind the charge port cover (the dark gray strip). The...