Engine Coolant Temperature.

There are 3 main jobs that the antifreeze in coolant performs to keep the engine coolant temperature normal:

1. It prevents the coolant from freezing during cold weather

2. It raises the boiling temperature of the coolant to prevent overheating during hot weather

3. It fights corrosion

The vehicles are equipped with an Engine Coolant Temperature (ECT) Sensor screwed into the engine's block or cylinder head, which determines the temperature of the engine coolant. If the operating temperature exceeds what your owner's manual says is acceptable (usually between 200 and 230 degrees F), it's time to check the cooling system checked to avoid overheating, and a possible breakdown.