As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE SMELLED AND VISIBLE IN CABIN. PERFORMED TSM 21-00-00-810-801A, NO OIL SOURCE OR LEAK FOUND IN APU COMPARTMENT OR ELBOW DUCT. PERFORMED TSM 71-00-00-810-801-A, CONTAMINATION NOT PRESENT FROM EITHER ENGINE. NO SMOKE PRESENT DURING EVENT. PERFORMED OPS TEST OF THE SDF SYSTEM IAW AMM 26-10-00. OPS CHECKED GOOD. NO DEFEFCTS NOTED. ACFT RETURNED TO SERVICE.