As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
STRONG BURNING SMELL IN AFT OF CABIN REPORTED BY F/A`S. NO EVIDENCE OF SMOKE. RAN ENG AT CLIMB PWR FOR 5 MIN AND DUPLICATED SMELL IN AFT CABIN AND GALLEY AND COCKPIT. PERFORMED BURNOUT PROCEDURE PER 21-00-01. FOUND NO OIL IN AIR CONDITIONING SYSTEM. BOTH ACMS SPIN FREELY AND NO OIL RESIDUE IN DUCTS. RAN ENG AFTER CHANGING WTR SOCKS AND CABIN FILTER AND DOING BURNOUT. ALL CHECKS GOOD.