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/InstallationBattery Inspection [Skyactiv G 2.0]
WARNING:
Since battery acid is toxic, be careful when handling the battery.
Since battery acid is highly corrosive, be careful not to allow it to contact
clothing or the vehicle.
In case battery acid contacts skin, eyes, or clothing, flush it immediately
with running wa ...
Start Stop Unit Removal/Installation
CAUTION:
If configuration is not performed when the start stop unit is replaced with
a new one, the vehicle specification information is not stored in the start
stop unit and the system will not operate normally.
When performing configuration, it is necessary to read the vehicl ...
Air Cleaner
Purpose, Function
Prevents engine internal damage caused by penetration of dust or foreign
material.
Construction
The air cleaner is installed in front of the battery.
The air cleaner consists of the air cleaner case, air cleaner cover, and
air cleaner element ...