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/InstallationAuxiliary Jack/Usb Port Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the upper console..
3. While pressing the auxiliary jack/USB port. tabs in the direction of the arrows
(1) shown in the figure, press the auxiliary jack/USB port. in the direction of
the arrow (2) to detach the auxiliary jack/USB port. tab ...
Wiper/Washer System Personalization
A customize function has been adopted which switches the auto wiper system
between operable/inoperable.
Using Mazda Modular Diagnostic System (M-MDS)
The auto wiper function can be enabled or disabled using the Mazda Modular
Diagnostic System (M-MDS). Refer to the Workshop M ...
Air Mix Actuator Inspection [Full Auto Air Conditioner]
CAUTION:
If the lever position exceeds the operation range shown in the figure, the
circuit in the actuator could be damaged. Always perform an actuator operation
inspection with the lever movement within the range shown in the figure.
Driver-side
1. Connect battery positive vol ...