1999 GMC Suburban Owner's Manual - Page 253

yellowblue Cooling System (Gasoline Engine) When you decide it's safe to lift the hood, here's what you'll see: CAUTION: If your vehicle has air conditioning, the auxiliary electric engine cooling fan under the hood can start up even when the engine is not running and can injure you. Keep hands, clothing and tools away from any underhood electric fan. If the coolant inside the coolant recovery tank is boiling, don't do anything else until it cools down. A. Coolant Recovery Tank B. Radiator Pressure Cap C. Engine Fan(s) 5-11