2003 Chevrolet Astro Owner's Manual - Page 250

Cooling System When you decide it's safe to lift the hood, here's what you'll see: The coolant level should be at the ADD mark. A If it isn't, you may have a leak at the pressure cap or in the radiator hoses, heater hoses, radiator, water pump or somewhere else in the cooling system. A. Coolant Recovery Tank B. Radiator Pressure Cap C.Engine Cooling Fan If the coolant inside the coolant recovery tank is boiling, don't do anything else until it cools down. The vehicle should be parked on a level surface. Heater and radiator hoses, and other engine parts, can be very hot. Don't touch them. If you do, you can be burned. Don't run the engine if therea leak. If you run is the engine,it could lose all coolant. That could cause an engine fire, and you could be burned.Get any leak fixed before you drive the vehicle. 5-33