What was found
AIRCRAFT WAS GNDED. AIR INTERRUPT, EMER DECLARED, LANDING UNEVENTFUL & ACFT OVERWEIGHT. DURING CLIMB THE COCKPIT MASTER CAUTION LAVATORY SMOKE LIGHT ILLUMINATED. FLIGHT ATTENDANTS REPORTED THE FIRST CLASS LAVATORY SMOKE LIGHT ILLUMINATED & AURAL WARNING SOUNDED. ATTENDANTS CONFIRMED NO VISIBLE SMOKE OR FIRE. WARNINGS LASTED APPROX 30 SECONDS. CONFIRMED NO EVIDENCE OF SMOKE & ACCOMPLISHED OPERATIONAL CHECK OF FIRST CLASS LAVATORY SMOKE DETECTOR IAW AMM 26-14-00-710-802 WITH NO FAULTS FOUND.