Boat alarm

by ariel
(michigan city indiana)

every time we turn the key to start the boat, before the motor starts an alarm goes off. We do not know why it comes on. we have added automatic trans. fluid, sternal fluid, both were low, however it alarms and then stops once we start the engine. any ideas, we are scratching our heads. the boat is a 1992 sunray sundance 270. we just bought the boat.