What does it mean?
The cooling system keeps engine operating temperature in a specified range. If the engine runs too cold, excessive emissions and poor fuel mileage may result. If the engine runs hotter than normal, detonation or engine overheating can occur. This often results in severe engine damage. The following are main cooling system components: Thermostat The thermostat allows the engine to come up to operating temperature quickly and then maintain a minimum temperature.
Radiator Coolant from the engine flows through the radiator and air flow across the fins of the radiator. This air dissipates heat from the coolant before it returns to the engine. Water Pump The water pump is belt driven off the engine. Just as the name implies, the water pump is designed to pump coolant throughout the engine. Cooling fans Cooling fans can be either of the mechanical or electrical variety. Most modern vehicles use electric fans.
When the engine slightly exceeds the operating temperature (or when the A/C is switched on) the fans engage. Coolant Temperature Sensor (ECT) The PCM sends the ECT a reference voltage. The sensor then varies the voltage according to engine temperature. The PCM monitors this change in voltage and using the information to control various system outputs. Hoses The cooling system employs different diameter hoses to connect the various system components.
There are two main hoses – the upper and the lower – that connect the radiator to the rest of the system. Heater Core The heater core is small radiator tucked away under the dash. Air passes over the heater core and into the engine compartment to keep it warm. A typical Cooling System