What was found
DURING DESCENT, PASSENGER REPORTED A BURNING ODOR. NO SMOKE WAS APPARENT AND NO ODOR IN COCKPIT. AFTER LANDING, PASSENGERS STATED THAT IT CAME FROM THE REAR CABIN AREA AND HAD A BURNING ELECTRICAL, OR ACRID ODOR. A FAINT ODOR OF OIL COULD BE SMELLED WITH PACKS RUNNING. COMPLETED ACM FAULT ISOLATION TESTS. TEST DETERMINED WATER SEPARATOR SOCKS TO BE CLEANED. CLEANED WATER SEPARATOR SOCKS INSTALLED AND PERFORMED DUCT BURN OUT PROCEDURES. NO ODOR IN CABIN NOTICED. ALL WORK IAW MM 21-52-00.