As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. CABIN ODOR IN THE FLIGHT DECK AND AFT CABIN DURING DESCENT. AUXILIARY POWER UNIT OFF. ODOR STOPPED UPON LANDING. REMOVED AND REPLACED APU OIL PUMP DIFFERENTIAL PRESSURE SWITCH IAW AMM 49-91-15. OPERATIONAL CHECK GOOD.