As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DURING DESCENT THROUGH CLOUD LAYER AT 3,000FT, AN ODOR CAME FROMTHE AIR VENTS ON THE FLIGHT DECK. IT WAS MUSTY. IT STOPPED SHORTLY AFTER. IT RETURNED AFTER TURNING ON THE APU BLEED AIR AFTER PARKING AFTER THE APU HAD BEEN ON FOR OVER 5 MINUTES. THE ODOR DID NOT OCCUR WITH THE APU RUNNING AT DEPARTURE AIRPORT. MAINTENANCE PERFORMED SOF TROUBLESHOOTING IAW J/C 26L00021001. NO FINDINGS.