For 1990-2009 cars

## Operating Modes Oldsmobile

The driver may select the following different modes of operation:

• | OFF

• | AUTO

• | R. DEFOG

• | FLOOR/WINDSHIELD

• | MID/FLOOR

• | MID

• | FLOOR

• | FRONT DEFROST

• | RECIRC

When operating in AUTO mode, the heater and A/C programmer may operate in several different modes:

• | MID/FLOOR

• | MID

• | FLOOR

• | FRONT DEFROST

The heater and A/C programmer may also access 3 purge modes when certain conditions exist.

### Off Setting

When the climate control system operates in the dual zone mode and you select OFF, the dual zone function will turn off. This turns off the blower motor and the A/C compressor.

When the vehicle is moving, air flowing over the vehicle increases the air pressure just ahead of the windshield. This forces air into the outside air inlet, through the heater and A/C module assembly, and out through the floor and windshield outlets.

By energizing the air inlet actuator, the heater and A/C programmer attempts to match the inside and the driver selected temperatures. Since the compressor is not running, the system air may be warmed, but not cooled.

### Auto Setting

The blower motor turns ON. The heater and A/C programmer automatically controls the blower speed. The driver may override the automatic blower control by turning the fan speed control.

The heater and A/C programmer evaluates the information supplied by the following components:

• | The heater and the A/C control

• | The network of sensors

The heater and A/C programmer determines whether one of the following modes is required:

• | MID/FLOOR

• | MID

• | FLOOR

The programmer energizes the mode actuator in order to enter this mode.

The information that is supplied to the programmer determines whether the system will draw the outside air in or recirculate the inside air.

### Floors/Windshield Setting

The A/C compressor activates if the outside temperature is above 5°C (41°F). The A/C compressor runs in order to keep the evaporator core at about 1°C (33°F).

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Open the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the floor outlets.

The blower pulls the outside air into the system. The air is cooled and dehumidified. The adjusted air is heated as necessary. Air is delivered to the floor and to the windshield outlets.

### Mid/Floor Setting

The A/C compressor activates if the outside temperature is above 5°C (41°F). The A/C compressor operates in order to keep the evaporator core at about 1°C (33°F).

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Close the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the A/C vents and the floor outlets.

The blower pulls the outside air into the system. The air is cooled and dehumidified. The adjusted air is heated as necessary. Air is delivered to the floor and to the instrument panel outlets.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

### Mid Setting

The A/C compressor activates if the outside temperature is above 5°C (41°F). The A/C compressor operates in order to keep the evaporator core at about 1°C (33°F).

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Close the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the A/C vents.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

### Floor Setting

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Close the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the heater vents.

• | Direct a small amount of air through the windshield outlets.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

### Front Defrost Setting

The blower motor turns ON. You may manually adjust the blower speed. The A/C compressor activates if the outside temperature is above 5°C (41°F). The air compressor runs in order to keep the evaporator core at about 1°C (33°F).

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Open the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct some of the air through the floor outlets.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

You cannot turn off the A/C compressor.

### Recirc Setting

When you select the RECIRC mode, the programmer energizes the air inlet actuator. The air inlet actuator positions the air inlet valve to the recirculate position.

The RECIRC mode operates in the following modes:

• | FLOOR/WINDSHIELD

• | MID/FLOOR

• | MID

• | FLOOR

RECIRC is not allowed during the FRONT DEFROST mode. This may cause windshield fogging.

The RECIRC function will operate for the entire ignition cycle. Pressing the RECIRC button with the system OFF, will return the system to the last setting (prior to the system being turned OFF).

### Dual Zone Setting

Adjust the passenger control head in order to select the dual zone mode. The programmer energizes the driver and the passenger air mix valves independently. The passenger may operate the passenger temperature control knob in order to request a warmer or a cooler temperature on the passenger side of the vehicle. The programmer energizes the passenger air mix valve actuator in order to increase or decrease the passenger side discharge temperature, if the set temperature is not the maximum hot or the maximum cold setting.

## Operating Modes Buick

The driver may select the following different modes of operation:

• | OFF

• | AUTO

• | VENT

• | FLOOR/WINDSHIELD

• | MID/FLOOR

• | MID

• | FLOOR

• | FRONT DEFROST

When operating in AUTO mode, the heater and A/C programmer may operate in several different modes:

• | MID/FLOOR

• | MID

• | FLOOR

• | FRONT DEFROST

The heater and A/C programmer may also access 3 purge modes when certain conditions exist.

### Off Setting

When the climate control system operates in the dual zone mode and you press the OFF button once, the dual zone function will turn off. If you press the OFF button twice, the whole climate control system will turn off. This action turns off the blower motor and the A/C compressor.

When the vehicle is moving, air flowing over the vehicle increases the air pressure just ahead of the windshield. This forces air into the outside air inlet, through the heater and A/C module assembly, and out through the floor and windshield outlets.

The heater and A/C programmer operates the air mix valve. The heater and A/C programmer attempts to match the inside and the driver selected temperatures. Since the compressor is not running, the system air may be warmed, but not cooled.

### Auto Setting

The blower motor turns ON. The heater and A/C programmer automatically controls the blower speed. The driver may override the automatic blower control by pressing the fan speed switch.

The heater and A/C programmer evaluates the information supplied by the following components:

• | The heater and the A/C control

• | The network of sensors

The heater and A/C programmer determines whether one of the following modes is required:

• | MID/FLOOR

• | MID

• | FLOOR

The programmer energizes the mode actuator to enter this mode.

The information that is supplied to the programmer determines whether the system will draw the outside air in or recirculate the inside air.

### Floors/Windshield Setting

The A/C compressor activates if the outside temperature is above 5°C (41°F). The A/C compressor runs in order to keep the evaporator core at about 1°C (33°F), as long as you do not press the VENT button.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Open the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the floor outlets.

The blower pulls the outside air into the system. The air is cooled and dehumidified. The adjusted air is heated as necessary. Air is delivered to the floor and to the windshield outlets.

### Mid/Floor Setting

The A/C compressor activates if the outside temperature is above 5°C (41°F). The A/C compressor operates in order to keep the evaporator core at about 1°C (33°F), as long as you do not press the VENT button.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Close the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the A/C vents and the floor outlets.

The blower pulls the outside air into the system. The air is cooled and dehumidified. The adjusted air is heated as necessary. Air is delivered to the floor and to the instrument panel (IP) outlets.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

### Mid Setting

Access the MID mode by using the heater and A/C programmer when operating in AUTO mode.

The A/C compressor activates if the outside temperature is above 5°C (41°F). The A/C compressor operates in order to keep the evaporator core at about 1°C (33°F), as long as you do not press the VENT button.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Close the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the A/C vents.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

### Floor Setting

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Close the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct air through the heater vents.

• | Direct a small amount of air through the windshield outlets.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

### Front Defrost Setting

The blower motor turns ON. You may manually adjust the blower speed using the fan switch. The A/C compressor activates if the outside temperature is above 5°C (41°F). The air compressor runs in order to keep the evaporator core at about 1°C (33°F).

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Open the defroster door.

• | Position the air inlet door to the outside air position.

• | Position the A/C door in order to direct some of the air through the floor outlets.

The heater and A/C programmer energizes the air mix actuators in order to perform the following functions:

• | Maintain the air discharge temperature.

• | Position the air mix valve accordingly.

You cannot turn off the A/C compressor.

### Recirc Setting

When you select the RECIRC mode, the programmer energizes the air inlet actuator. The air inlet actuator positions the air inlet valve to the recirculate position.

The RECIRC mode operates in the following modes:

• | FLOOR/WINDSHIELD

• | MID/FLOOR

• | MID

• | FLOOR

RECIRC is not allowed during the FRONT DEFROST mode. This may cause windshield fogging.

The RECIRC function will operate for the entire ignition cycle. Pressing the RECIRC button with the system OFF, will return the system to the last setting (prior to the system being turned OFF).

### Dual Zone Setting

Adjust the passenger control head in order to select the dual zone mode. The programmer energizes the driver and the passenger air mix valves independently. The passenger may operate the passenger temperature control knob in order to request a warmer or a cooler temperature on the passenger side of the vehicle. The programmer energizes the passenger air mix valve actuator in order to increase or decrease the passenger side discharge temperature, if the set temperature is not the maximum hot or the maximum cold setting.