Purpose
The expansion valve atomizes liquid refrigerant to facilitate cooling of the evaporator.
Function
The expansion valve reduces the pressure of liquid refrigerant rapidly to facilitate vaporization of the atomized refrigerant at the evaporator, and adjusts the refrigerant amount sent into the evaporator.
Construction
The expansion valve consists of the following parts:
Diaphragm
Temperature sensor
Shaft
Expansion valve body
Ball valve
Spring

Operation
Adjustment of the refrigerant amount supplied to the evaporator is performed by the ball valve opening angle in the expansion valve.
The opening angle adjustment is performed according to the balance of the following forces:

Refrigerant pressure (Pd) in diaphragm
Refrigerant gas pressure (PI) of evaporator under diaphragm
Spring force (Fs) pushing up ball valve
If the refrigerant gas temperature from the evaporator increases, the expansion valve increases the amount of refrigerant according to the following operations:

The temperature of the temperature sensor tightly sealed against the diaphragm increases.
The refrigerant in the diaphragm warms and the Pd increases.
If this Pd increases more than PI + Fs, the diaphragm is pressed down.
The shaft installed to the temperature sensor end presses down the ball valve.
The amount of refrigerant is increased.
If the refrigerant gas temperature from the evaporator decreases, the expansion valve decreases the amount of refrigerant flow according to the following operation:

The temperature of the temperature sensor tightly sealed against the diaphragm decreases.
The refrigerant temperature in the diaphragm decreases and the Pd decreases.
The Pd decreases less than PI + Fs.
The ball valve installed to the temperature sensor end is pressed up.
The amount of refrigerant is decreased.
Fail-safe
Function not equipped.
Evaporator Inspection
Expansion Valve Removal/InstallationThrottle Position (TP) Sensor Inspection
Voltage Inspection
CAUTION:
The inspection cannot be performed with this method correctly if there is
a malfunction of the APP sensor or throttle valve actuator. Verify that no DTCs
related to the APP sensor or throttle valve actuator are stored before the inspection.
NOTE:
...
Fuel Draining Procedure
WARNING:
Fuel line spills and leakage from the pressurized fuel system are dangerous.
Fuel can ignite and cause serious injury or death and damage. To prevent this,
complete the following inspection with the engine stopped.
Fuel is very flammable liquid. If fuel spills or leaks ...
Pre Tensioner Seat Belt [Standard Deployment Control System]
Purpose
The pre-tensioner seat belt retracts and tightens the seat belt webbing to
protect the front passengers during a collision.
Function
The pre-tensioner seat belts operate (deploy) based on the operation signal
from the SAS control module to instantly retract and tigh ...