2001 GMC Sierra 1500 Pickup Owner's Manual - Page 185

Low Coolant This message is displayed when the cooling system is low on coolant. Engine Overheated This message is displayed when the cooling system temperature gets too hot. The engine may overheat. See "Engine Coolant" in the Index and have your vehicle serviced as soon as you can. Check Coolant Temp This message is displayed when the cooling system temperature gets hot. This message will be displayed after the air conditioning system has automatically turned off for the engine coolant protection mode. See "Engine Overheating" in the Index for further information. Reduced Engine Power (V8 Gasoline Engines Only) This message is displayed when the cooling system temperature gets too hot and the engine further enters the engine coolant protection mode. If your vehicle is equipped with the 8.1L engine, this light may come on because of an electronic throttle control system fault. See "Engine Overheating" in the Index for further information. Check the coolant temperature gage and the coolant level. See "Engine Coolant" and "Engine Coolant Temperature Gage" in the Index. See "Engine Overheating" in the Index for further information. 2-102