Cripes, this doesn't sound like much fun.
Just in case someone else comes across this thread with slightly different symptoms, I have gotten "Automated Emergency Braking Disabled" when my MX was fully charged, and then put on Autopilot. I think it was because there was no re-gen, the car couldn't predict the effect of braking/easting off the accelerator properly. I had the error message constantly until the next time I got into the car. I've not seen it again since.