As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: LAVATORY SMOKE LIGHT ILLUMINATED DURING CRUISE QRH PROCEDURE PERFORMED NO SMOKE PRESENT VERIFIED ATTENDANT. LIGHT ILLUMINATED 3 SEPARATE TIMES. CHECKED AND ACCOMPLISHED FIRST CLASS LAVATORY SMOKE DETECTOR AND NOTED TEST OK PER AMM 26-14-00.