Ventilation

General

All Cayenne Models have a heating and air conditioning system that meets maximum comfort demands. The design, functions and special qualities of the ventilation, air conditioning and heating systems are detailed in the section "Climate Control".

85 Ventilation

Air flow (Air Ducts)

All Cayenne models have a charcoal filter that filters particles and pollen out of the outside air before the air enters the vehicle. The filter is integrated into the heating unit. It is located in front of the evaporator and can be pulled out of the heating unit, in the passenger side floor, for service purposes.

Should the outside air quality deteriorate, circulating air can be manually switched on. The 2 or 4 zone Climate Controls also have an air quality sensor that has standard values for "automatic switch to circulating air" (AUTO Circulating Switch).

The outside air that goes into the heating unit and is heated to the desired temperature is directed into the passenger area. A system of fixed and moveable vents provides the airflow. There are vents in the control panel that distribute the air to the driver and passenger sides. These also dehumidify and defrost the front windshield. Extra and individual personal vents are also in the rear middle console and in the B-pillar covering. Floor vents are also located under the front seats.

2-Zone Climate Control







With 4-Zone Climate Control, the following diagram shows the additional air ducts that enable air distribution in all zones.







The heating unit for the additional Climate Control (4 zones) is located behind the left sidewall covering in the trunk area. Only the front driver side and passenger side vents will receive airflow from the standard Climate Control. The vents for the second row seats will receive airflow only from the trunk air conditioning. The air distribution to the vents of the B-columns, the middle console and the floor will be controlled by this additional Climate Control. The separate rear air ducts run underneath the trunk floor. They fan out and replace the air distribution over the door coverings and the middle console.

Air and Flap Control (Heating Unit)







Before the outside or circulating air can flow into the various air ducts and be distributed into the passenger area, the entire airflow will be blown through the evaporator by the fans. When the air conditioning is on, the air is cooled and dehumidified. Following this, depending on the setting on the heating or air conditioning control panel, the entire flow of air, or only part of this air will flow through the heater core in the heating unit. This air will then move through the separate flaps in the heating unit (air mixing area) to be directed to the air ducts and distributed.

With the 2 zone and 4 zone automatic climate control, there is also a potentiometer on the flap motor for the fresh and circulating air flap. This sends the current flap position to the control module.

The design of the front HVAC unit housing is almost identical for the 4 zone or 2 zone Climate Control. With 4 zone Climate Control, the flap for the mid and side vents as well as the floor vents (please see the block diagram) can be controlled independently of each other. There are also three additional flap motors. They can be found on the right side of the air mixing area across from the flap motors in positions 2,3 and 4 (see diagram 8_04_03).

In the rear heating unit the fan flap motors for air volume and the temperature mixing flap is integrated. Because the heating unit is designed symmetrically, the motors for the right and left sides are directly across from each other. The actuators or the mid vents are directly on the air duct, right before the vent openings in the rear mid console. The flap motors for the floor/B-columns vents are located on the separators for each separate air duct.







After removing both screws (in "a"), the rear heating unit can be tipped slightly forward. In this position one can reach the fan motor or the actuators for the left side.