AIR CONDITIONING SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The air conditioning system consists of the following parts:

      Component Function
      Air Conditioning Amplifier Assembly Transmits and receives data to and from the switches and sensors, and controls the air conditioning system.
      Cooler Compressor Assembly Performs suction, compression and discharge of refrigerant gas.
      Blower with Fan Motor Sub-assembly A brushless motor is used to achieve a compact and lightweight assembly.
      Cooler Condenser 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-II (SFA-II) heater radiator is used for compactness and high performance.
      No. 1 Cooler Evaporator Sub-assembly A Revolutionary super-slim Structure (RS) type cooler evaporator sub-assembly is used for compactness and high performance.
      Evaporator Temperature (No. 1 Cooler Thermistor) Detects the temperature of the cool air past the cooler evaporator sub-assembly and transmits the data to the air conditioning amplifier assembly.
      Ambient Temperature Sensor (Thermistor Assembly) Detects ambient temperature and outputs it to the air conditioning amplifier assembly.
      Room Temperature Sensor (Cooler Thermistor) Detects room temperature and outputs it to the air conditioning amplifier assembly.
      Air Conditioning Thermistor Assembly Detects glass temperature, glass surroundings temperature and glass humidity, and outputs them to the air conditioning amplifier assembly.
      Solar Sensor (Automatic Light Control Sensor) Detects the changes in the amount of solar energy and outputs them to the air conditioning amplifier assembly.
      PTC Heater (Quick Heater Assembly)* Consists of a Positive Temperature Coefficient (PTC) element, an aluminum fin and a brass plate.
      Damper Servo Sub-assembly Receives the operation signals from the air conditioning amplifier assembly, operates the motor, and opens and closes the dampers.
      Air Refiner Element Removes pollen, other particles and smell to provide a comfortable interior space.
      Air Conditioning Pressure Sensor Detects the refrigerant pressure and sends the data to the air conditioning amplifier assembly.
      ECM Receives the signals from the engine coolant temperature sensor and transmits them to the air conditioning amplifier assembly.

      *: Models with PTC Heater

  2. SYSTEM CONTROL


    1. Control List

      Control Function
      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 Based on the temperature set at the temperature control switch, the neural network control calculates the outlet air temperature based on the input signals from various sensors.
      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 achieved.
      The temperature setting for the driver, front passenger and rear passenger is controlled independently in order to provide a separate vehicle interior temperature for the right, left and rear sides of the vehicle. Thus, air conditioning control that accommodates occupant preferences has been achieved.
      Blower Control Controls the blower motor in accordance with the airflow volume that has been calculated by neural network control based on the input signals from various sensors.
      Automatically increases the blower level when the defroster is on.
      Air Outlet Control Automatically switches the air outlets in accordance with the outlet mode that has been calculated by neural network control based on the input signals from various sensors.
      In accordance with the engine coolant temperature, outside air temperature, amount of sunlight, cabin air humidity, required blower, outlet temperature and vehicle speed conditions, this control automatically switches the blower outlet to FOOT/DEF mode to prevent the windows from becoming fogged when the outside air temperature is low.
      Air Inlet Control Automatically controls the air inlet control damper to achieve the calculated outlet air temperature that is required.
      Drives the servo motor (for air inlet) in accordance with the operation of the air inlet control switch and moves the dampers to the FRESH or RECIRC position.
      Cooler Compressor Control Through the calculation of the target evaporator temperature based on various sensor signals, the air conditioning amplifier assembly optimally controls the discharge capacity by regulating the opening extent of the solenoid control valve.
      Turns the air conditioning on automatically by pressing the AUTO button when the blower is on and the air conditioning is off.
      Evaporator Control When set to automatic, cooler compressor variable capacity operation is controlled to save power. When set to manual, cooler compressor variable capacity operation is controlled for maximum cooling to dehumidify air and prevent the windows from fogging up.
      PTC Heater Control*

      When the engine switch is turned on (IG), and the blower motor is turnedon, 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).
      Rear Window Defogger Control

      • Switches the rear defogger and outside rear view mirror heaters on for 15 minutes when the rear defogger and mirror heater switch is pressed.

      • Switches the rear defogger and outside rear view mirror heaters off if the button is pressed while they are operating.
      Outside Temperature Indication Control Based on the signals from the thermistor assembly, this control calculates the outside temperature, this value is then corrected in the air conditioning amplifier, and shown on the multi-information display.
      Diagnosis A Diagnostic Trouble Code (DTC) is stored in memory when the air conditioning amplifier assembly detects a problem with the air conditioning system.

      *: 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.

        A018GMFE13

    3. 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).

        A018GB3E01
        *1 PTC Heater Output
        *2 Engine Coolant Temperature

  3. DIAGNOSIS


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