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/InstallationFlywheel Inspection [C66 M R]
1. Remove the flywheel..
2. Perform the following procedures to inspect the flywheel.
If there is any malfunction or it exceeds the maximum specification, replace
the flywheel..
a. Inspect the surface that contacts the clutch disc for scratches, nicks, and
discoloration.
...
Precaution [Dynamic Stability Control (DSC)]
1. The ABS warning light and/or brake system warning light and/or TCS/DSC indicator
light and/or TCS OFF indicator light illuminate even when the system is normal.
Warning lights/Indicator lights that may illuminate and/or flash
Cases in which the light may ill ...
High Mount Brake Light Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the liftgate upper trim..
3. Remove the rear spoiler..
4. Disconnect the connector.
5. While pressing the high-mount brake light tab in the direction of arrow (1)
shown in the figure, press the high-mount brake light in the direction ...