Air Conditioning System (for Manual Air Conditioning System)

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Manual Air Conditioning System): SYSTEM DIAGRAM

SYSTEM DIAGRAM





Communication Table





*1: for 2GR-FE

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Manual Air Conditioning System): SYSTEM DESCRIPTION

SYSTEM DESCRIPTION

1. GENERAL
(a) The air conditioning system has the following controls.





- *1: for 2GR-FE
- *2: without DEF, F/D mode

2. MODE POSITION AND DAMPER OPERATION
(a) Mode Position and Damper Operation





Functions of Main Dampers





3. AIR OUTLETS AND AIRFLOW VOLUME
(a) Air Outlets and Airflow Volume









The size of each circle o indicates the ratio of airflow volume.
4. A/C COMPRESSOR
(a) General:
(1) The A/C compressor is a continuously variable capacity type in which its capacity can be varied in accordance with the cooling load of the air conditioning system.
(2) The compressor consists of the A/C pulley, shaft, lug plate, swash plate, piston, shoe, crank chamber, cylinder and solenoid valve.
(3) The A/C pulley with built-in magnetic clutch has an A/C lock sensor that detects whether the A/C compressor is locked.*1
(4) A solenoid valve that is provided to enable the suction pressure to be controlled as desired.
(5) The internal valve is provided to improve the A/C compressor durability under the high speed and large thermal load conditions. The internal valve is integrated into the solenoid valve.
- *1: for 2GR-FE

(b) Solenoid Valve Operation:
(1) The crank chamber is connected to the suction passage. A solenoid valve is provided between the suction passage (low pressure) and the discharge passage (high pressure).
(2) The solenoid valve operates under duty cycle control in accordance with the signals from A/C amplifier.
(3) When the solenoid valve closes (solenoid coil is energized), a difference in pressure is created and the pressure in the crank chamber decreases. Then, the pressure that is applied to the right side of the piston becomes greater than the pressure that is applied to the left side of the piston. This compresses the spring and tilts the swash plate. As a result, the piston stroke increases and the discharge capacity also increases.
(4) When the solenoid valve opens (solenoid coil is not energized), the difference in pressure disappears. Then, the pressure that is applied to the left side of the piston becomes the same as the pressure that is applied to the right side of the piston. Thus, the spring elongates and eliminates the tilt of the swash plate. As a result, there is no piston stroke, and the discharge capacity is reduced.
(c) Internal Valve Operation:
(1) The internal valve operates when the A/C compressor speed has increased rapidly, the A/C compressor speed is high, or when thermal load has suddenly changed. As a result, the A/C compressor capacity is reduced and the durability of the A/C compressor increases.
5. A/C LOCK SENSOR (for 2GR-FE)
The A/C lock sensor sends A/C pulley speed signals to the A/C amplifier. The A/C amplifier determines whether the A/C compressor is locked or not by using those signals and engine speed signals.
6. EVAPORATOR TEMPERATURE SENSOR
The evaporator temperature sensor detects the temperature of the cool air immediately through the evaporator in the form of resistance changes, and outputs it to the A/C amplifier.
7. BLOWER MOTOR
The front blower motor has a built-in blower controller, and is controlled using duty control performed by the A/C amplifier.
8. BUS CONNECTOR (AIR CONDITIONING HARNESS)
(a) A BUS connector is used in the wire harness connection that connects the servo motor from the A/C amplifier.





(b) Each BUS connector has a built-in communication/driver IC which communicates with each servo motor connector, actuates the servo motor, and has a position detection function. This enables bus communication for the servo motor wire harness, for a more lightweight construction and a reduced number of wires.





9. SERVO MOTOR
The pulse pattern type servo motor consists of a printed circuit board and a servo motor. The printed circuit board has three contact points, and can transmit two ON-OFF signals to the A/C amplifier based on the difference of the pulse phases. The BUS connector can detect the damper position and movement direction with this signal.





10. AMBIENT TEMPERATURE SENSOR
The ambient temperature sensor detects the outside temperature based on changes in the resistance of its built-in thermistor and sends a signal to the A/C amplifier.
11. A/C PRESSURE SENSOR
The A/C pressure sensor detects the refrigerant pressure and outputs it to the A/C amplifier in the form of voltage changes.