Main A/C-Heater System
WARNING: This page is about a different car, the 2002 Mercury Villager. However, it is still accessible from the selected car via links, so may be relevant.
The main system uses blend air method to provide conditioned air to vehicle interior. Temperature blending is controlled by temperature blend door, which regulates amount of cool airflow through or around heater core. An internal microcomputer analyzes inputs from various sources to provide optimum system performance. The A/C pressure (high and low) switches turn compressor on and off to maintain desired cooling and prevent evaporator freezing.