2005 INFINITI FX35 air condition

ATC-12
PRECAUTIONS
Revision: 2005 July 2005 FX
CAUTION:
The new and former refrigerant connections use different O-ring configurations. Never confuse O-
rings since they are not interchangeable. If a wrong O-ring is installed, refrigerant will leak at, or
around, the connection.
O-Ring Part Numbers and Specifications
WARNING:
Make sure all refrigerant is discharged into the recycling equipment and the pressure in the system is
less than atmospheric pressure. Then gradually loosen the discharge side hose fitting and remove it.
CAUTION:
When replacing or cleaning refrigerant cycle components, observe the following.

When the compressor is removed, store it in the same way as 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 tube, 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 dented portion 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.
Connection type Piping connection point Part number QTY O-ring size
New Low-pressure pipe 1 to low-pressure pipe 2 (One-touch joint) 92473 N8221 2 16
Low-pressure pipe 2 to expansion valve 92473 N8210 1 16
High-pressure pipe 1 to high-pressure pipe 2 (One-touch joint) 92471 N8221 2 8
High-pressure pipe 3 to expansion valve 92471 N8210 1 8
High-pressure pipe 2 to high-pressure pipe 3 (One-touch joint) 92471 N8221 2 8
Condenser to high-pressure flexible hose (One-touch joint) 92472 N8221 2 12
Condenser to high-pressure pipe 1 (One-touch joint) 92471 N8221 2 8
Low-pressure flexible hose to low-pressure pipe 1 (One-touch joint) 92473 N8221 2 16
Compressor to low-pressure flexible hose 92474 N8210 1 19
Compressor to high-pressure flexible hose 92472 N8210 1 12
Liquid tank to condenser pipe Inlet
92471 N8210 1
8
Outlet 1
Former Refrigerant pressure sensor to condenser J2476 89956 1 10
Expansion valve to evaporator Inlet 92475 71L00 1 12
Outlet 92475 72L00 1 16
Lubricant name : Nissan A/C System Oil Type S
Part number : KLH00-PAGS0

ATC-22
REFRIGERATION SYSTEM
Revision: 2005 July 2005 FX
V-6 Variable Displacement CompressorAJS001BE
GENERAL INFORMATION
1. The V-6 variable compressor differs from previous units. The vent temperatures of the V-6 variable com-
pressor do not drop too far below 5 °C (41 °F) when:
Evaporator intake air temperature is less than 20 °C (68 °F).
Engine is running at speeds less than 1,500 rpm.
This is because the V-6 compressor provides a means of “capacity” control.
2. The V-6 variable compressor provides refrigerant control under varying conditions. During cold winters, it may not produce high refrigerant pressure discharge (compared to previous units) when used with air
conditioning systems.
3. A “clanking” sound may occasionally be heard during refrigerant charge. The sound indicates that the tilt angle of the wobble (swash) plate has changed and is not a malfunction.
4. For air conditioning systems with the V-6 compressor, the clutch remains engaged unless: the system main switch, fan switch or ignition switch is turned OFF. When ambient (outside) temperatures are low or
when the amount of refrigerant is insufficient, the clutch is disengaged to protect the compressor.

LUBRICANT ATC-27
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LUBRICANTPFP:KLG00
Maintenance of Lubricant Quantity in CompressorAJS00149
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 engine, and set 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 engine.
>> GO TO 3.
3. CHECK REPLACEMENT PART
Should the compressor be replaced?
YES >> GO TO AT C - 2 9 , "LUBRICANT ADJUSTING PROCEDURE FOR COMPRESSOR REPLACE-
MENT" .
NO >> GO TO AT C - 2 8 , "
LUBRICANT ADJUSTING PROCEDURE FOR COMPONENTS REPLACE-
MENT EXCEPT COMPRESSOR" .
Name : NISSAN A/C System Oil Type S
Part number : KLH00-PAGS0

ATC-30
AIR CONDITIONER CONTROL
Revision: 2005 July 2005 FX
AIR CONDITIONER CONTROLPFP:27500
Description of Air Conditioner LAN Control SystemAJS0014A
The LAN (Local Area Network) system consists of unified meter and A/C amp., mode door motor, air mix door
motor and intake door motor.
A configuration of these components is shown in the diagram below.
System ConstructionAJS0014B
A small network is constructed between the unified meter and A/C amp., air mix door motor, mode door motor
and intake door motor. The unified meter and A/C amp. and motors are connected by data transmission lines
and motor power supply lines. The LAN network is built through the ground circuits of each door motor.
Addresses, motor opening angle signals, motor stop signals and error checking messages are all transmitted
through the data transmission lines connecting the unified meter and A/C amp. and each door motor.
The following functions are contained in LCUs built into the air mix door motor, the mode door motor and the
intake door motor.

Address

Motor opening angle signals

Data transmission

Motor stop and drive decision

Opening angle sensor (PBR function)

Comparison

Decision (Unified meter and A/C amp. indicated value and motor opening angle comparison)
OPERATION
The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp.
sends mode door, air mix door and intake door opening angle data to the mode door motor LCU, air mix door
motor LCU and intake door motor LCU.
The mode door motor, air mix door motor and intake door motor read their respective signals according to the
address signal. Opening angle indication signals received from the unified meter and A/C amp. and each of
the motor position sensors is compared by the LCUs in each motor with the existing decision and opening
angles. Subsequently, HOT/COLD, DEF/VENT and FRESH/RECIRCULATION operation is selected. The new
selection data is returned to the unified meter and A/C amp.
SJIA0262E
RJIA1747E

AIR CONDITIONER CONTROL ATC-31
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Revision: 2005 July 2005 FX
TRANSMISSION DATA AND TRANSMISSION ORDER
Unified meter and A/C amp. data is transmitted consecutively to each of the door motors following the form
shown in figure below.
Start:
Initial compulsory signal sent to each of the door motors.
Address:
Data sent from the unified meter and A/C amp. are selected according to data-based decisions made by the
air mix door motor, mode door motor and intake door motor.
If the addresses are identical, the opening angle data and error check signals are received by the door motor
LCUs. The LCUs then make the appropriate error decision. If the opening angle data have no error, door con-
trol begins.
If an error exists, the received data are rejected and corrected data received. Finally, door control is based
upon the corrected opening angle data.
Opening Angle:
Data that shows the indicated door opening angle of each door motor.
Error Check:
Procedure by which sent and received data is checked for errors. Error data are then compiled. The error
check prevents corrupted data from being used by the air mix door motor, the mode door motor and the intake
door motor. Error data can be related to the following symptoms.

Malfunction of electrical frequency

Poor electrical connections

Signal leakage from transmission lines

Signal level fluctuation
RJIA1748E

ATC-32
AIR CONDITIONER CONTROL
Revision: 2005 July 2005 FX
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 door is 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.
OUTLET DOOR CONTROL
The outlet door is automatically controlled by the temperature setting, ambient temperature, in-vehicle temper-
ature, intake temperature and amount of sunload.
RJIA1749E

AIR CONDITIONER CONTROL ATC-33
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Revision: 2005 July 2005 FX
MAGNET CLUTCH CONTROL
When A/C switch or DEF switch is pressed, unified meter and A/C amp. inputs compressor ON signal to BCM.
BCM sends compressor ON signal to ECM, via CAN communication line.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant-pressure sen-
sor signal, throttle angle, etc.). If it judges compressor can be turned ON, it sends compressor ON signal to
IPDM E/R, via CAN communication line.
Upon receipt of compressor ON signal from ECM, IPDM E/R turns air conditioner relay ON to operate com-
pressor.
When sending compressor ON signal to IPDM E/R via CAN communication line, ECM simultaneously sends
compressor feedback signal to unified meter and A/C amp. via CAN communication line.
Unified meter and A/C amp., then, uses input compressor feedback signal to control air inlet.
SELF-DIAGNOSIS SYSTEM
The self-diagnosis system is built into the unified meter and A/C amp. to quickly locate the cause of symp-
toms.
RJIA1957E

ATC-34
AIR CONDITIONER CONTROL
Revision: 2005 July 2005 FX
Description of Control SystemAJS0014C
The control system consists of input sensors, switches, the unified meter and A/C amp. (microcomputer) and
outputs. The relationship of these components is shown in the figure below:
Control OperationAJS0014D
DISPLAY SCREEN
Displays the operational status of the system.
RJIA1958E
RJIA1959E