As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED APU SOV OPEN STATUS MESSAGE IN FLIGHT AFTER APU SHUTDOWN. CREW RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE TROUBLESHOT APU, REMOVED AND REPLACED APU POWER FUEL PUSHBUTTON SWITCH AND PERFORMED CHECKS USING AIRCRAFT MAINTENANCE MANUALS. AIRCRAFT RELEASED FOR SERVICE.