PRECAUTIONS
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CAUTION:
When replacing or cleaning refrigerant cycle components, observe the following.
When the compressor is removed, store it in the same way at it is when mounted on the car. Fail-
ure to do so will cause lubricant to enter the low-pressure chamber.
When connecting tubes, always use a torque wrench and a back-up wrench.
After disconnecting tubes, immediately plug all openings to prevent entry of dirt and moisture.
When installing an air conditioner in the vehicle, connect the pipes at the final stage of the opera-
tion. Never remove the seal caps of pipes and other components until just before required for con-
nection.
Allow components stored in cool areas to warm to working area temperature before removing seal
caps. This prevents condensation from forming inside A/C components.
Thoroughly remove moisture from the refrigeration system before charging the refrigerant.
Always replace used O-rings.
When connecting tubes, apply lubricant to circle of the O-rings shown in illustration. Be careful
not to apply lubricant to threaded portion.
O-ring must be closely attached to the groove of tube.
When replacing the O-ring, be careful not to damage O-ring and tube.
Connect tube until a click can be heard, then tighten the nut or bolt by hand until snug. Make sure
that the O-ring is installed to tube correctly.
After connecting line, perform leak test and make sure that there is no leakage from connections.
When the refrigerant leaking point is found, disconnect that line and replace the O-ring. Then
tighten connections of seal seat to the specified torque.
Precautions for Servicing CompressorBJS000F8
Plug all openings to prevent moisture and foreign matter from entering.
When the compressor is removed, store it in the same position at it is when mounted on the car.
When replacing or repairing compressor, follow “Maintenance of Lubricant Quantity in Compres-
sor” exactly. Refer to AT C - 2 1 , "
Maintenance of Lubricant Quantity in Compressor" .
Keep friction surfaces between clutch and pulley clean. If the surface is contaminated, with lubri-
cant, wipe it off by using a clean waste cloth moistened with thinner.
After compressor service operation, turn the compressor shaft by hand more than five turns in
both directions. This will equally distribute lubricant inside the compressor. After the compressor
is installed, let the engine idle and operate the compressor for one hour.Lubricant name : Nissan A/C System Oil Type S
RHA861F
REFRIGERATION SYSTEM
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REFRIGERATION SYSTEMPFP:KA990
Refrigerant CycleBJS000FF
REFRIGERANT FLOW
The refrigerant flows form the compressor through the condenser with liquid tank, through the evaporator, and
back to the compressor. The refrigerant evaporation in the evaporator is controlled by an externally equalized
expansion valve, located inside the evaporator case.
FREEZE PROTECTION
To prevent evaporator frozen up, the evaporator air temperature is monitored, and the voltage signal to the
unified meter and A/C amp. will make the A/C relay go OFF and stop the compressor.
Refrigerant System ProtectionBJS000FG
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively high- or low-pressure by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above, or falls below the specifications, the refrig-
erant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM.
ECM makes the A/C relay go OFF and stops the compressor when pressure on the high-pressure side
detected by refrigerant pressure sensor is over about 2,746 kPa (27.46 bar, 28 kg/cm
2 , 398 psi), or below
about 134 kPa (1.34 bar, 1.4 kg/cm
2 , 20 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 unusual level [more than 3,727 kPa (37.27 bar,
38 kg/cm
2 , 540 psi)], the release port on the pressure relief valve automatically opens and releases refriger-
ant into the atmosphere.
RJIA1745E
LUBRICANT
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LUBRICANTPFP:KLG00
Maintenance of Lubricant Quantity in CompressorBJS000FI
The lubricant in the compressor circulates through the system with the refrigerant. Add lubricant to compres-
sor when replacing any component or after a large refrigerant leakage occurred. It is important to maintain the
specified amount.
If lubricant quantity is not maintained properly, the following malfunctions may result:
Lack of lubricant: May lead to a seized compressor
Excessive lubricant: Inadequate cooling (thermal exchange interference)
LUBRICANT
LUBRICANT RETURN OPERATION
Adjust the lubricant quantity according to the test group shown below.
1. CHECK LUBRICANT RETURN OPERATION
Can lubricant return operation be performed?
A/C system works properly.
There is no evidence of a large amount of lubricant leakage.
CAUTION:
If excessive lubricant leakage is noted, never perform the lubricant return operation.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. PERFORM LUBRICANT RETURN OPERATION, PROCEEDING AS FOLLOWS
1. Start the engine, and set to the following conditions:
–Engine speed: Idling to 1,200 rpm
–A/C switch: ON
–Blower speed: Max. position
–Temp. control: Optional [Set so that intake air temperature is 25 to 30°C (77 to 86°F).]
–Intake position: Recirculation (REC)
2. Perform lubricant return operation for about 10 minutes.
3. Stop the engine.
>> GO TO 3.
3. CHECK REPLACEMENT PART
Should the compressor be replaced?
YES >> GO TO AT C - 2 2 , "LUBRICANT ADJUSTING PROCEDURE FOR COMPRESSOR REPLACE-
MENT" .
NO >> GO TO AT C - 2 2 , "
LUBRICANT ADJUSTING PROCEDURE FOR COMPONENTS REPLACE-
MENT EXCEPT COMPRESSOR" . Name : NISSAN A/C System Oil Type S
ATC-26
AIR CONDITIONER CONTROL
Stop Signal:
At the end of each transmission, a stop operation, in-operation, or internal malfunction message is delivered to
the unified meter and A/C amp. This completes one data transmission and control cycle.
AIR MIX DOOR CONTROL (AUTOMATIC TEMPERATURE CONTROL)
The air mix doors are automatically controlled so that in-vehicle temperature is maintained at a predetermined
value by the temperature setting, ambient temperature, in-vehicle temperature and amount of sunload.
FAN SPEED CONTROL
Blower speed is automatically controlled by the temperature setting, ambient temperature, in-vehicle tempera-
ture, intake temperature, amount of sunload and air mix door position.
With pressing AUTO switch, the blower motor starts to gradually increase air flow volume.
When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from flow-
ing.
INTAKE DOOR CONTROL
The intake doors are automatically controlled by the temperature setting, ambient temperature, in-vehicle tem-
perature, intake temperature, amount of sunload and ON/OFF operation of the compressor.
MODE DOOR CONTROL
The mode door is automatically controlled by the temperature setting, ambient temperature, in-vehicle temper-
ature, intake temperature and amount of sunload.
RJIA1749E
AIR CONDITIONER CONTROL
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Control OperationBJS000FM
DISPLAY SCREEN
The operation status of the system is displayed on the screen.
TEMPERATURE CONTROL SWITCH (POTENTIO TEMPERATURE CONTROL) (DRIVER SIDE)
The set temperature is increased or decreased with this switch.
TEMPERATURE CONTROL SWITCH (POTENTIO TEMPERATURE CONTROL) (PASSENGER
SIDE)
The set temperature for passenger side is increased or decreased with this switch.
When the temperature switch is pressed, the DUAL switch indicator will automatically illuminate.
AUTO SWITCH
The compressor, intake doors, air mix doors, mode doors and blower speed are automatically controlled
so that the in-vehicle temperature will reach, and be maintained at the set temperature selected by the
operator.
When pressing AUTO switch, air inlet, air outlet, fan speed, and discharge air temperature are automati-
cally controlled.
A/C SWITCH
Compressor is ON or OFF with this switch.
(Pressing the A/C switch when the A/C switch is ON will turn OFF the A/C switch and compressor.)
FAN SWITCH
The blower speed is manually controlled with this switch. Seven speeds are available for manual control
(as shown on the display screen).
RJIA3235E
ATC-30
AIR CONDITIONER CONTROL
When fan control switch (DOWN) is pressed for approximately 2 seconds or longer or press fan control
switch when blower fan motor operates at 1st speed, A/C system will turn OFF (The compressor and
blower are OFF, the intake doors and the mode doors are automatically controlled).
INTAKE SWITCH
When intake switch is ON, FRE LED turns ON, and air inlet is fixed to FRE.
When press intake switch again, REC LED turns ON, and air inlet is fixed to REC.
When intake switch is pressed for approximately 1.5 seconds or longer, FRE and REC LEDs blink twice.
Then, automatic control mode is entered. Inlet status is displayed by LED even during automatic con-
trolled.
When FRE LED is turned ON, shifting mode position to D/F or DEF, or when compressor is turned from
ON to OFF, intake switch is automatically turned OFF (fixed to FRE mode). REC mode can be re-entered
by pressing intake switch again, and then compressor is turned ON. (Except D/F or DEF position)
MODE SWITCH
The air discharge outlets is controlled with this switch.
DEFROSTER (DEF) SWITCH
Mode doors are set to the defrost position with this switch. Also, intake doors are set to the outside air position,
and compressor turns ON.
REAR WINDOW DEFOGGER SWITCH
When illumination is ON, rear window is defogged.
DUAL SWITCH
When the DUAL switch indicator is illuminated, the driver-side and passenger-side temperature can each
be set independently.
When the DUAL switch indicator is not illuminated, the driver-side setting temperature is applied to both
sides.
Fail-safe FunctionBJS000FN
If a communication error exists between the unified meter and A/C amp. and the A/C and AV switch for 30 sec-
onds or longer, air conditioner is controlled under the following conditions:
Compressor : ON
Air outlet : AUTO
Air inlet : FRE (Fresh)
Blower fan speed : AUTO
Set temperature : Setting before communication error occurs
Display : OFF
TROUBLE DIAGNOSIS
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How to Perform Trouble Diagnosis for Quick and Accurate RepairBJS000FS
WORK FLOW
SYMPTOM TABLE
*1AT C - 5 4 , "Operational Check"
SHA900E
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System.ATC-56, "
Power
Supply and
Ground Circuit for
Auto Amp."
A/C system cannot be controlled.Go to Integrated Display System.
Go to Integrated Color Display System.AV- 5 8 , "
Unable to
Operate System
with A/C and AV
Switch" (Inte-
grated display sys-
tem), AV-97,
"Unable to Oper-
ate System with A/
C and AV Switch"
(Integrated color
display system)
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. (LAN)AT C - 6 3 , "
Mode
Door Motor Cir-
cuit"Mode door motor does not operate normally.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor. (LAN)ATC-66, "
Air Mix
Door Motor Cir-
cuit"Air mix door motor does not operate nor-
mally.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. (LAN)AT C - 6 9 , "
Intake
Door Motor Cir-
cuit" Intake door motor does not operate normally.
Blower motor operation is malfunctioning. Go to Trouble Diagnosis Procedure for Blower Motor.ATC-72, "
Blower
Motor Circuit"
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch.AT C - 7 8 , "Magnet
Clutch Circuit"
Insufficient cooling Go to Trouble Diagnosis Procedure for Insufficient Cooling.AT C - 8 4 , "Insuffi-
cient Cooling"
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.AT C - 9 1 , "Insuffi-
cient Heating"
Noise Go to Trouble Diagnosis Procedure for Noise.ATC-92, "Noise"
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis.AT C - 9 4 , "Self-
diagnosis"
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.AT C - 9 5 , "Memory
Function"
ATC-46
TROUBLE DIAGNOSIS
Self-diagnosis FunctionBJS000FX
DESCRIPTION
The self-diagnosis system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to appli-
cable sections (items) for details. Shifting from usual control to the self-diagnosis system is accomplished by
starting the engine (turning the ignition switch ON) and pressing A/C switch for at least 5 seconds. The A/C
switch must be pressed within 10 seconds after starting the engine (ignition switch is turned ON). This system
will be canceled by either pressing AUTO switch or turning the ignition switch OFF. Shifting to the next step is
accomplished by means of pressing temperature control switch (driver side), as required.
Additionally sifting from STEP-5 to AUXILIARY MECHANISM is accomplished by means of pressing (fan)
control switch (UP).
SJIA1670E