As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN REQUIRED EN ROUTE SHUTTING DOWN APU LOW OIL PRESSURE LIGHT WAS ILLUMINATED. AFTER SHUT DOWN LIGHT WENT OUT. NO MASTER CAUTION LIGHT ILLUMINATED. PERFORMED FIM TASK 49 90 00 810 803. THRU STEPS F (3). REMOVED AND REPLACED LOW OIL PRESSURE SWITCH REF MM 49 94 22. OPS CHECK LEAK CHECK OK. NO FAULTS LOGGED.