Truck Repair: alarm

Question
we have a 1997 Dump Truck Ford L9000 with a 3406 engine and there is an alarm that continues to go off every few seconds in the cab.  What could cause this

Answer
What kind of alarm we have check engine light, no lights just a buzzer, is it hydraulic brakes or air brakes. If air is your pressure good in the air tanks. Does it cause the engine to shut down. Have you checked all the fluids make sure coolant reservoir is full and oil good. I know some dump trucks and trucks with wetline kits have buzzers on them if the pto is left on.