As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACRID CABIN ODOR THROUGHOUT AIRCRAFT MOST NOTICABLE DURING APPROACH. REMOVED AND REPLACED APU. COMPLIED WITH ENVIRONMENTAL CONTROL SYSTEM PER 26L00021004. NO ODORS NOTED. SUP WILL SUBMIT ROOT CAUSE INFORMATION UPON RECEIPT OF TEAR DOWN REPORT FROM HONEYWELL. APU WAS A CONFIRMED FAILURE PER VENDOR TEARDOWN REPORT.