As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BURNING ODOR AT AFT CABIN, NOTICED BY CREW MEMBERS & AFT F/A CONTROL PANEL APPEARS TO BE HOT TO TOUCH. INSPECTED F/A PANEL NO DEFECT NOTED CREW GROUND RAN AIRCRAFT WITH BLEEDS ON, NO ABNORMAL ODOR NOTED. DEACTIVATED PSU AT 8DF DUE TO INTERMIT CHIM ACTIVATION IAW SPECIAL PROCEDURES 23.3. REMOVED AND REPLACED PSU, OPS CHECK GOOD.