As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED, RECEIVED AN APU OIL PRESSURE MESSAGE IN FLIGHT. BECAUSE THE RIGHT IDG WAS DEFERED THE CREW DIVERTED TO TYS LANDING WITHOUT INCIDENT. MAINTENANCE TROUBLESHOT THE APU OIL SYSTEM USING THE AIRCRAFT MAITENANCE MANUALS. THE LOW OIL PRESSURE SWITCH PLUG WAS FOUND CONTAMINATED, WAS CLEANED, AND RE-INSTALLED. CHECKS WERE MADE USING THE AIRCRAFT MAINTENANCE MANUALS AND AIRCRAFT WAS RELEASED FOR SERVICE.