As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RECEIVED LAVATORY SMOKE INDICATION WITH BLEEDS ON, PACKS CLOSED AND APU OFF, SMOKE WAS NOTICED FROM PSU GASPERS. CIRCUIT BREAKERS PULLED PER AIRCRAFT OPERATING MANUAL AND SMOKE AND SMELL DISAPPEARED. RETURNED TO JFK. REMOVED AND REPLACED RIGHT HAND ENGINE DUCT ASSEMBLY IAW EMB AMM 36-11-00. OPERATIONAL CHECK GOOD WITH NO SMOKE NOTED - PERFORMED FUNCTIONAL CHECK FLIGHT. RETURNED AIRCRAFT TO SERVICE