How do you handle exception handling in embedded environments, where it's usually not possible to display a full error message?

• http://www.embedded.com/design/prototyping-and-development/4007615/An-exception-primer
  • in a car, some CEL/OBDII codes are thrown, or if things get really bad, a limp-home mode is engaged
  • on Chicago car-parking pay boxes, errors are indicated by a light that flashes a certain number of times
• https://www.quora.com/How-is-exception-handling-used-in-embedded-software <-- I don't agree with these