As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB FLIGHT ATTENDANT REPORTED LIGHT SMOKE IN CABIN. FLIGHT ATTENDANT DISCHARGED A HALON FIRE EXTINGUISHER IN THE AFT RIGHT LAV. FLIGHT CREW RETURNED AC TO DEPARTURE AIRPORT AND PERFORMED AN UNEVENTFUL LANDING. NO EVIDENCE OF A FIRE WAS FOUND. MAINTENANCE DID FIND THE APU OIL COOLER LEAKING OIL. APU DEACTIVATED AND SCHEDULED FOR REPLACEMENT. FOLLOW UP INFORMATION, REFERENCE CONTROL NUMBER 0202119952 SUBMITTED 6/28/02.