The document describes the layout and components of a vehicle cooling system, including a PWM fan assembly, water pump, EGR cooler, coolant ports, fan flap door, radiator, and coolant reservoir. It also compares the cooling system for different engine models, noting the D20DT engine model is equipped with an E-EGR cooler and improved water pump capacity due to additional coolant lines in the cylinder block. A schematic diagram shows coolant flow from the cylinder block through various components like the oil cooler, heater, water pump, cylinder head, and radiator before returning to the water pump.