Automatic Modes

The automatic HVAC system will warm up/cool down and maintain the interior temperature of the vehicle by controlling the A/C compressor clutch, blower motor, air temperature, mode and recirculation actuators to achieve the desired temperature. For fully automatic operation, both the blower and mode switches must be in the AUTO position. Blower speeds will change automatically based on inputs to the HVAC control module. The HVAC control module will always come back to the last settings after an ignition cycle or, if equipped, to the last settings of the driver by pressing the UNLOCK button on the remote keyless entry fob and placing the ignition in RUN.

In cold temperatures, the automatic HVAC system will provide heat in the most efficient manner. On cold engine start-up, the blower motor will start out at low speed and will increase speeds as engine coolant temperature increases. To warm the interior quickly, maximum heat mode is used where the blower is at maximum speed, floor mode, air temperature is in full hot and outside air is being drawn in. The vehicle operator can select the extreme warm setting of 32°C (90°F), but the system will not warm the vehicle any faster. Once the desired temperature is reached, the blower motor, mode, recirculation and temperature will be adjusted automatically by the HVAC control module.

Setting the temperature to 32°C (90°F) will lock the HVAC control module in maximum speed, floor mode, air temperature in full hot and outside air is being drawn in. The AUTO LED will not illuminate at this extreme temperature setting. The HVAC control module will not control the HVAC system automatically until the set temperature is lowered from 32°C (90°F). Once the temperature setting is lowered, the AUTO switch will have to be pressed again to activate the automatic HVAC system. The AUTO LED will then illuminate.

In warm temperatures, the automatic HVAC system will provide A/C in the most efficient manner. On initial engine start-up, the blower motor will come on at low blower speeds to purge the HVAC module of moisture. To cool the interior quickly, maximum cool mode is used where the blower is at maximum speed, vent mode, air temperature actuator is in full cold and the recirculation actuator is drawing air from inside the vehicle. The vehicle operator can select the extreme cool setting of 16°C (60°F), but the system will not cool the vehicle any faster. Once the desired temperature is reached, the blower motor, mode, recirculation and temperature will be adjusted automatically by the HVAC control module.

Setting the temperature to 16°C (60°F) will lock the HVAC control module in maximum speed, vent mode, air temperature in full cold and recirculation mode. The AUTO LED will not illuminate at this extreme temperature setting. The HVAC control module will not control the HVAC system automatically until the set temperature is raised from 16°C (60°F). Once the temperature setting is raised, the AUTO switch will have to be pressed again to activate the automatic HVAC system. The AUTO LED will then illuminate.