AIR CONDITIONING SYSTEM CONTROL AIR CONDITIONING CONTROL

  1. FUNCTION OF MAIN COMPONENTS

    1. The main components of the air conditioning system have the following functions:

      Component

      Function

      Compressor Assembly with Pulley

      A rotary vane type cooler compressor assembly is used.

      No. 1 Cooler Thermistor

      The No. 1 cooler thermistor detects the temperature of the cool air immediately after the evaporator in the form of resistance changes, and outputs it to the air conditioning control assembly

      Blower with Fan Motor Assembly

      The blower motor with fan sub-assembly has a built-in blower controller, and is controlled using duty control performed by the air conditioning control assembly.

      Blower Resistor

      The blower resistor controls the blower motor with fan sub-assembly based on changes in the signal sent by the air conditioning control assembly.

      Servo Motor

      Each control pulse received by the stepper motor is transformed into rotation of the rotor of the stepper motor by a specific angle called a step. This motor consists of 4 coils and a rotor consisting of a ferrite bar with 6 teeth. When a coil is supplied, it becomes an electromagnet and attracts the ferrite bar which naturally follows the magnetic field.

      Thermistor Assembly

      The thermistor assembly detects the outside temperature based on changes in the resistance of its built-in thermistor and sends a signal to the combination meter assembly.

      Cooler (Solar Sensor) Thermistor

      The cooler (solar sensor) thermistor detects (in the form of changes in the current that flows through the built-in photo diode) the changes in the amount of sunlight and outputs these sunlight strength signals to the air conditioning control assembly.

      Pressure Switch

      When a refrigerant pressure malfunction is detected, the pressure switch suspends A/C on signals sent from the air conditioning control assembly to the ECM and cuts the current to the magnet clutch to stop the compressor.

  2. SYSTEM CONTROL

    1. The automatic air conditioning system uses the following controls:

      Control

      Outline

      Air Outlet Control

      In accordance with the engine coolant temperature, ambient air temperature, amount of sunlight, required blower, outlet temperature and vehicle speed conditions, this control automatically switches the blower outlet to foot/defroster mode to prevent the windows from becoming fogged up when the ambient air temperature is low.

      Air Inlet Control

      Automatically controls the air inlet control damper to help achieve the calculated outlet air temperature that is required.

      Drives the air inlet control servo motor according to the operation of the air inlet control switch and moves the dampers to the fresh or recirculation position.

      Compressor Control

      Through the calculation of the target evaporator temperature based on various sensor signals, the air conditioning control optimally controls discharge capacity by regulating the opening extent of the compressor solenoid valve.

      Rear Defogger Control

      Refer to Rear Defogger System.

      Defroster Control

      Defroster control logic is used to improve defroster performance.

      Diagnosis

      A Diagnostic Trouble Code (DTC) is stored in memory when the air conditioning control assembly detects a problem with the air conditioning system.

  3. DIAGNOSIS

    1. The air conditioning control assembly has a diagnosis function. It stores any operation failures in the memory in the form of Diagnostic Trouble Codes (DTCs). For details, refer to the Repair Manual.