What was found
(CAN) SMOKE ALARM IN LAVATORY SOUNDED ALONG WITH SMELL OF SMOKE AFTER PUSH BACK. AIRCRAFT RETURNED TO GATE. INSPECTED LAVATORY, WASTE CONTAINER, LIGHTING, LAVATORY PUMP, BEHIND CEILING AND UNDER SINK, NO FAULT FOUND. LAVATORY DEACTIVATED PER MINIMUM EQUIPMENT LIST. CIRCUIT BREAKER PULLED FOR LIGHTING AND LAVATORY. RIGHT HAND AIR CONDITIONING AIR CYCLING MACHINE AND COALESCER BAG (P/N 18084-1) REPLACED.