AIR CONDITIONING SYSTEM


  1. FUNCTION OF MAIN COMPONENTS

    Component Function Air Conditioning Type
    Single Dual
    Air Conditioning Control Assembly Allows operation and adjustment of the air conditioning system via switches. ○ ○
    Air Conditioning Amplifier Assembly Transmits and receives data between the switches and sensors. ○ ○
    Compressor with Motor Assembly Performs suction, compression and discharge of refrigerant gas and is driven by the electric motor. ○ ○
    Blower Motor with Fan Sub-assembly High magnetic force magnets and ball bearings are used to achieve a compact and lightweight assembly. ○ ○
    Cooler Condenser (Condenser with Receiver Assembly) A Multi-Flow (MF)-IV sub-cool condenser is used to improve heat exchange efficiency. ○ ○
    Heater Radiator Unit Sub-assembly A Straight Flow Aluminum (SFA)-II heater radiator is used for compactness and high performance. ○ ○
    No. 1 Cooler Evaporator Sub-assembly A Revolutionary super-Slim structure (RS) evaporator is used for compactness. ○ ○
    No.1 Cooler Thermistor Detects the temperature of the cool air past the No. 1 cooler evaporator sub-assembly and transmits the data to the air conditioning amplifier assembly. ○ ○
    Thermistor Assembly Detects ambient temperature and outputs it to the combination meter assembly. ○ ○
    Cooler (Room Temperature Sensor) Thermistor Detects room temperature and outputs it to the air conditioning amplifier assembly. ○ ○
    Cooler (Solar Sensor) Thermistor Detects the changes in the amount of solar energy and outputs them to the air conditioning amplifier assembly. ○ ○
    PTC Heater (Quick Heater Assembly)*1 Consists of Positive Temperature Coefficient (PTC) elements, aluminum fins, and brass plates. ○ ○
    Air Mix Damper Servo Sub-assembly Receives temperature setting signals via the air conditioning amplifier assembly, operates the motor, and opens and closes the air mix damper. ○ ○
    No. 2 Air Mix Damper Servo Sub-assembly - ○
    Recirculation Damper Servo Sub-assembly Receives fresh-air/recirculation selector operation signals via the air conditioning amplifier assembly, operates the motor, and opens and closes the fresh-air/recirculation damper. ○ ○
    Mode Damper Servo Sub-assembly Receives mode selector operation signals via the air conditioning amplifier assembly, operates the motor, and opens and closes the mode damper. ○ ○
    Clean Air Filter (Air Refiner Element) Removes pollen and other particles to provide a comfortable interior space. ○ ○
    Air Conditioner Pressure Sensor Detects the refrigerant pressure and sends data to the air conditioning amplifier assembly. ○ ○
    ECM Receives signals from the E.F.I. engine coolant temperature sensor and transmits them to the air conditioning amplifier assembly. ○ ○
    Inverter with Converter Assembly*1 Transmits the power control unit stage signal to the air conditioning amplifier assembly. ○ ○
    ECO MODE Switch (Combination Switch Assembly) Sends the ECO MODE Switch operation signal to the air conditioning amplifier assembly. ○ ○
    Radio and Display Receiver Assembly*2 Temporarily displays current information of the air conditioning system when the air conditioning control panel is operated. ○ ○

    Tech Tips

    ○: Equipped

    -: Not equipped

    *1: Models with PTC heater

    *2: Models with touch screen system or display audio system

  2. SYSTEM CONTROL


    1. Control List

      Control Outline Air Conditioning Type
      Single Dual
      Neural Network Control This control is capable of effecting complex control by artificially simulating the information processing method of the nervous system of living organisms in order to establish a complex input/output relationship that is similar to a human brain. ○ ○
      Outlet Air Temperature Control In compliance with the temperature set at the temperature control switch, the neural network control calculates the outlet temperature based on the input signals from various sensors. In addition, corrections in accordance with the signals from the No. 1 cooler thermistor and the E.F.I. engine coolant temperature sensor are added to control the outlet air temperature. ○ ○
      Left and Right Independent Control The temperature setting for the driver and front passenger is controlled independently in order to provide a separate vehicle interior temperature for the right and left sides of the vehicle. Thus, air conditioning control that accommodates occupant preferences has been realized. - ○
      Blower Control Controls the blower motor with fan sub-assembly in accordance with the airflow volume that has been calculated by the neural network control based on the input signals from various sensors. ○ ○
      Air Outlet Control Automatically switches the outlets in accordance with the outlet mode ratio that has been calculated by the neural network control based on the input signals from various sensors. ○ ○
      Air Inlet Control Automatically controls the air inlet control damper in accordance with the airflow volume that has been calculated by the neural network control. ○ ○
      Electric Inverter Compressor Control Compressor Speed Control The air conditioning amplifier assembly calculates the target speed of the compressor based on the target evaporator temperature (which is calculated by the temperature control switch, cooler (room temperature sensor) thermistor, outside temperature sensor (thermistor assembly), and cooler (solar sensor) thermistor) and the actual evaporator temperature that is detected by the evaporator temperature sensor (No. 1 cooler thermistor) in order to control the compressor speed. ○ ○
      The air conditioning amplifier assembly calculates the target evaporator temperature, which includes corrections based on the temperature control switch, cooler (room temperature sensor) thermistor, outside temperature sensor (thermistor assembly), cooler (solar sensor) thermistor, and evaporator temperature sensor (No. 1 cooler thermistor). Accordingly, the air conditioning amplifier assembly controls the compressor speed to an extent that would not inhibit the proper cooling performance or defogging performance. ○ ○
      Turns the air conditioning ON automatically when the AUTO button is pressed when the blower is ON and the air conditioning is OFF. ○ ○
      Decreases the compressor speed in order to ensure quietness when the vehicle is stopped or the engine is off. ○ ○
      Refrigerant Volume Detection Control Judges a shortage of refrigerant volume based on signals from each sensor and informs the user by turning off the indicator light of the A/C switch. ○ ○
      PTC Heater Control*

      When the power switch is turned on (IG), and the blower motor is turned on, the air conditioning amplifier assembly turns on the PTC heater (quick heater assembly) if the following conditions are met.


      • E.F.I. engine coolant temperature is below specified temperature.

      • Ambient temperature is below specified temperature.

      • Tentative air mix damper opening angle is above the specified value (MAX HOT).

      		 ○ ○
      Electric Engine Water Pump Control The air conditioning amplifier assembly calculates the flow rate value required for the electric engine water pump assembly in accordance with the engine coolant temperature and air mix damper opening degree and sends it to the ECM. ○ ○
      ECO Mode Control When the ECO mode switch (combination switch assembly) is turned on, the air conditioning amplifier assembly limits the air conditioning system performance. ○ ○
      Blower Customization Control During automatic air conditioning operation, the air volume can be adjusted in 3 levels using the FAST SOFT switch: MEDIUM → SOFT (small air volume) → FAST (large air volume). ○ ○
      Self-diagnosis The air conditioning amplifier assembly has a self-diagnosis function. It stores any operation malfunctions in memory in the form of Diagnostic Trouble Codes (DTCs). ○ ○

      Tech Tips

      ○: Equipped

      -: Not equipped

      *: Models with PTC heater

    2. Neural Network Control


      1. Previously, in automatic air conditioning systems without neural network control, the air conditioning amplifier assembly determined the required outlet air temperature and blower air volume in accordance with the calculation formula that has been obtained based on information received from the sensors. However, because the senses of a person are rather complex, a given temperature is sensed differently, depending on the environment in which the person is situated. For example, a given amount of solar radiation can feel comfortably warm in a cold climate, or extremely uncomfortable in a hot climate. Therefore, as a technique for effecting a higher level of control, a neural network has been adopted in the automatic air conditioning system. With this technique, the data that has been collected under varying environmental conditions is stored in the air conditioning amplifier assembly. The air conditioning amplifier assembly can then effect control to provide enhanced air conditioning comfort.

      2. The neural network control consists of neurons in the input layer, intermediate layer and output layer. The input layer neurons process the input data of the ambient temperature, the amount of sunlight, and the room temperature based on the outputs of the switches and sensors, and output them to the intermediate layer neurons. Based on this data, the intermediate layer neurons adjust the strength of the links among the neurons. The sum of these is then calculated by the output layer neurons in the form of the required outlet temperature, solar correction, target airflow volume, and outlet mode control volume. Accordingly, the air conditioning amplifier assembly controls the servo motors and blower motor in accordance with the control volumes that have been calculated by the neural network control.

        A01KE6DE11

    3. Refrigerant Volume Detection Control


      1. The air conditioning amplifier assembly judges the volume of refrigerant from the ambient temperature, refrigerant pressure and the temperature of the cool air just past the No. 1 cooler evaporator sub-assembly. When the air conditioning amplifier assembly judges that there is a refrigerant shortage, it turns off the indicator light of the A/C switch. At that time, the compressor with motor assembly stops operating.

        A01KE6UE01

    4. PTC Heater Control


      1. The output of the PTC heater (quick heater assembly) is controlled by the air conditioning amplifier assembly in accordance with the engine coolant temperature, engine speed, air mix setting, and electrical load (generator assembly power ratio).

        A01KE3WE01
        *1 PTC Heater Output
        *2 Engine Coolant Temperature

    5. ECO Mode Control


      1. During ECO mode control, the air conditioning amplifier assembly restricts the air conditioning system performance under specified conditions, thus improving fuel economy.

      2. ECO mode control is activated when the ECO mode switch (combination switch assembly) is pushed, and then restricts the air conditioning system performance as described below.

        Control Outline
        Inside/Outside Air Switch Control Automatically switches the air inlet port to recirculation mode when the outside air temperature is equal to or higher than a predetermined temperature and reduces the power consumption.
        Blower Level Control Sets the blower level in AUTO mode lower than normal, and suppresses the power consumption.
        PTC Heater Control* Suppresses the power consumption.
        Heating Restriction Control Changes the air outlet temperature by entering ECO mode during heating and increases the amount of engine-off time when the drive mode is in ECO, thus improving fuel economy.
        Compressor Speed Restriction Control Restricts the maximum compressor speed during cooling and reduces the power consumption.

        *: Models with PTC heater

  3. DIAGNOSIS


    1. The air conditioning amplifier assembly has a self-diagnosis function. It stores any operation malfunctions in the air conditioning system in memory in the form of DTCs. For details, refer to the Repair Manual.