What was found
AIRCRAFT WAS NOT GROUNDED. ELECTRONIC CENTRALIZED AIRCRAFT MONITOR, LAVATORY SMOKE CAME ON AND THEN WENT OUT AFTER 20 SECONDS. CAME ON DURING DECENT. NO SMOKE NOTED IN LAVATORIES. ACCOMPLISHED LAVATORY SMOKE TEST, CABIN INTERCOMMUNICATION DATA SYSTEM SMOKE DETECTOR FUNCTION. NO FAULT NOTED OR DETECTED. CHECKED BOTH LAVATORIES FOR ANY SMOKE SMELL, BOTH CHECK NORMAL, PER AMM 36-10-00.