As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLOSED - ASH 2673 PIT. AIRCRAFT RETURNED TO THE GATE. CREW REPORTED SMOKE AND ODOR IN THE CABIN. MAINTENANCE ISOLATED THE PROBLEM TO THE APU. MAINTENANCE CLEARED THE CABIN OF SMOKE AND ODOR AND DEFERRED THE APU. 9/22/04 MAINTENANCE REMOVED AND REPLACED THE APU.