2007 Chevrolet Cobalt Owner's Manual - Page 170

Engine Coolant Temperature Warning Light The engine coolant temperature warning light will come on when the engine has overheated. Malfunction Indicator Lamp Check Engine Light Your vehicle has a computer which monitors operation of the fuel, ignition, and emission control systems. This system is called OBD II (On-Board Diagnostics-Second Generation) and is intended to assure that emissions are at acceptable levels for the life of the vehicle, helping to produce a cleaner environment. The check engine light comes on to indicate that there is a problem and service is required. Malfunctions often will be indicated by the system before any problem is apparent. This may prevent more serious damage to your vehicle. This system is also designed to assist your service technician in correctly diagnosing any malfunction. If this happens you should pull over and turn off the engine as soon as possible. See Engine Overheating on page 303 for more information. Notice: Driving with the engine coolant temperature warning light on could cause your vehicle to overheat. See Engine Overheating on page 303. Your vehicle could be damaged, and it might not be covered by your warranty. Never drive with the engine coolant temperature warning light on. This light will also come on when starting your vehicle. If it doesn't, have your vehicle serviced. 170