REFRIGERATION SYSTEM
Refrigerant Cycle
Refrigerant flow

The refrigerant from the compressor flows through the condenser with liquid tank, the evaporator and returns to the compressor. The refrigerant evaporation in the evaporator is controlled by an expansion valve.
Component Part Location

Refrigerant System Protection
Refrigerant pressure sensor
The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sensor, located on the condenser. If the system pressure rises above or falls below the specifications, the refrigerant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM.
The ECM then ceases to supply power to the A/C relay which disengages and stops the compressor when pressure on the high pressure side (as detected by refrigerant pressure sensor) is over approximately 2,746 kPa (28 kg/cm2, 398 psi), or below approximately 120 kPa (1.22 kg/cm2, 17.4 psi).
Pressure Relief Valve
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system increases to an abnormal level [more than 3,727 kPa (38 kg/ cm2, 540 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the atmosphere.
Preparation
Basic inspectionFog light switch
To turn the fog lights on, turn the headlight switch
to the position, then turn the fog
light
switch to the position.
To turn the fog lights on with the headlight switch
in the AUTO position, the headlights must be on,
then turn the fog light switch to the
position.
To turn the f ...
Magnet clutch control system
System Diagram
System Description
The A/C auto amp. controls A/C compressor operation by ambient temperature,
intake air temperature and
signal from ECM.
SYSTEM OPERATION
When the A/C switch, the AUTO switch, or the DEF switch is pressed, or when
shifting mode position to D/F,
the A/C ...
U1243 display unit
DTC Logic
Diagnosis Procedure
1.CHECK DISPLAY UNIT POWER SUPPLY AND GROUND CIRCUIT
Check display unit power supply and ground circuit
2.CHECK CONTINUITY OF COMMUNICATION CIRCUIT
Turn ignition switch OFF.
Disconnect display unit connector M142 and AV control unit
connector M163.
...