Automatic Operation

Dual Zone A/C System Description - Automatic Operation


One of these modes is a fully automatic dual zone mode which determines the following conditions (set by the driver):
^ The air intake mode (recirc or outside air)
^ The air delivery mode (upper, lower, bi-level and defog)
^ The fan speed
^ The discharge air temperature.

Press the AUTO button to place the entire system in the automatic mode. After a five second display of the current settings, only the word AUTO and the outside temperature will be shown on the digital display. The system will operate to achieve the set temperature as quickly as possible. If you have set the driver's temperature control at 16°C (60°F) or 32°C (90°F), the system will not operate automatically until a different temperature is selected. The AUTO control system works much more efficiently with the windows rolled up and the removable roof installed or the convertible top up.


A Typical Cold Weather Example:
The vehicle has been parked overnight in cold weather (below 0°C/32°F) and the driver has set the automatic temperature setting to 23°C (73°F). The system will automatically adjust the temperature output to maximum heating. The fan will start at low speed to avoid blowing cold air into the vehicle. The length of delay depends on the amount of time since the engine was last started, the outside temperature and the engine coolant temperature. As the coolant warms up, the fan speed will gradually increase. Air will flow to the floor with some air to the windshield to prevent fogging under most normal conditions.

As the interior of the vehicle warms up to the set temperature, the fan speed will decrease and the temperature output may become cooler. If the interior temperature continues to warm up due to heating from the sun or outside temperature increases, the system may switch to other air delivery modes (typically DEFOG or BI-LEVEL).

A Typical Hot Weather Example:
The vehicle has been parked all day in hot weather (above 21°C/70°F) and the driver has set the automatic temperature setting to 23°C (73°F). The system will automatically adjust the temperature output to maximum cooling. The fan will start at low speed momentarily to push the hot air to the floor of the vehicle and then go to a higher speed with cold airflow out of the instrument panel outlets. A small amount of airflow will continue through the lower air ducts to cool the floor area.

The air intake may start in the recirculated mode for maximum cooling performance. As the interior of the vehicle cools down to the set temperature, the fan speed will decrease and the temperature output may become warmer. The air intake may shift from recirculation to fresh air mode. If the interior temperature continues to cool down due to a decrease in the amount of heat the vehicle is absorbing from the sun or a decrease in the outside temperature, the system may switch to other air delivery modes (typically BI-LEVEL or DEFOG).