As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: THE FLIGHT CREW REPORTED THAT THE APU DISCHARGE LIGHT CAME ON IN FLIGHT AND THE FLIGHT CREW NOTED THAT THE APU APPEARS TO WORK NORMALLY -MAINTENANCE REPLACED THE APU FIRE EXTINGUISHER BOTTLE AND THE APU DISCHARGE LIGHT REMAINS OFF