2004 INFINITI FX35 sensor

ATC-2Revision: 2004 November 2004 FX35/FX45DUAL SWITCH (WITH LEFT AND RIGHT VEN-
TILATION TEMPERATURE SEPARATELY
CONTROL SYSTEM) .......................................... 35
Fail-safe Function ................................................... 36
Discharge Air Flow ................................................. 37
System Description ................................................. 38
SWITCHES AND THEIR CONTROL FUNCTION ... 38
CAN Communication System Description .............. 39
TROUBLE DIAGNOSIS ............................................ 40
CONSULT-II ............................................................ 40
CONSULT-II BASIC OPERATION ....................... 40
DATA MONITOR .................................................. 41
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ...................................................... 42
WORK FLOW ...................................................... 42
SYMPTOM TABLE .............................................. 42
Component Parts and Harness Connector Location ... 43
ENGINE COMPARTMENT .................................. 43
PASSENGER COMPARTMENT .......................... 44
Schematic ............................................................... 45
Wiring Diagram —A/C— ......................................... 46
Auto Amp. Terminals and Reference Value ............ 51
PIN CONNECTOR TERMINAL LAYOUT ............ 51
TERMINALS AND REFERENCE VALUE FOR
UNIFIED METER AND A/C AMP. ........................ 51
Self-diagnosis Function .......................................... 53
DESCRIPTION .................................................... 53
FUNCTION CONFIRMATION PROCEDURE ...... 54
AUXILIARY MECHANISM: TEMPERATURE
SETTING TRIMMER ........................................... 59
AUXILIARY MECHANISM: FOOT POSITION
SETTING TRIMMER ........................................... 60
AUXILIARY MECHANISM: INLET PORT MEM-
ORY FUNCTION ................................................. 60
Operational Check .................................................. 61
CHECKING MEMORY FUNCTION ..................... 61
CHECKING BLOWER ......................................... 61
CHECKING DISCHARGE AIR ............................ 61
CHECKING RECIRCULATION ............................ 62
CHECKING TEMPERATURE DECREASE ......... 62
CHECKING TEMPERATURE INCREASE .......... 62
CHECK A/C SWITCH .......................................... 62
CHECKING AUTO MODE ................................... 63
Power Supply and Ground Circuit for Auto Amp. ... 63
INSPECTION FLOW ........................................... 63
COMPONENT DESCRIPTION ............................ 64
DIAGNOSTIC PROCEDURE FOR A/C SYSTEM ... 64
LAN System Circuit ................................................ 66
DIAGNOSTIC PROCEDURE FOR LAN CIR-
CUIT .................................................................... 66
Mode Door Motor Circuit ........................................ 70
INSPECTION FLOW ........................................... 70
SYSTEM DESCRIPTION .................................... 71
COMPONENT DESCRIPTION ............................ 72
DIAGNOSTIC PROCEDURE FOR MODE
DOOR MOTOR ................................................... 72
Air Mix Door Motor Circuit ...................................... 73
INSPECTION FLOW ........................................... 73SYSTEM DESCRIPTION ..................................... 74
COMPONENT DESCRIPTION ............................ 75
DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR .................................................................. 75
Air Mix Door Motor PBR Circuit .............................. 75
DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR PBR .......................................................... 75
Intake Door Motor Circuit ........................................ 76
INSPECTION FLOW ............................................ 76
SYSTEM DESCRIPTION ..................................... 77
COMPONENT DESCRIPTION ............................ 78
DIAGNOSTIC PROCEDURE FOR INTAKE
DOOR MOTOR .................................................... 78
Blower Motor Circuit ................................................ 79
INSPECTION FLOW ............................................ 79
SYSTEM DESCRIPTION ..................................... 80
COMPONENT DESCRIPTION ............................ 81
DIAGNOSTIC PROCEDURE FOR BLOWER
MOTOR ................................................................ 81
COMPONENT INSPECTION ............................... 83
Magnet Clutch Circuit .............................................. 84
INSPECTION FLOW ............................................ 84
SYSTEM DESCRIPTION ..................................... 85
DIAGNOSTIC PROCEDURE FOR MAGNET
CLUTCH .............................................................. 85
COMPONENT INSPECTION ............................... 90
Insufficient Cooling .................................................. 91
INSPECTION FLOW ............................................ 91
PERFORMANCE TEST DIAGNOSIS .................. 93
PERFORMANCE CHART .................................... 95
TROUBLE DIAGNOSIS FOR UNUSUAL PRES-
SURE ................................................................... 96
DIAGNOSTIC PROCEDURE FOR INSUFFI-
CIENT COOLING ................................................. 98
Insufficient Heating ...............................................100
INSPECTION FLOW ..........................................100
Noise .....................................................................101
INSPECTION FLOW ..........................................101
Self-diagnosis .......................................................102
INSPECTION FLOW ..........................................102
Memory Function ..................................................103
INSPECTION FLOW ..........................................103
Ambient Sensor Circuit .........................................104
COMPONENT DESCRIPTION ..........................104
AMBIENT TEMPERATURE INPUT PROCESS .104
DIAGNOSTIC PROCEDURE FOR AMBIENT
SENSOR ............................................................104
COMPONENT INSPECTION .............................106
In-vehicle Sensor Circuit .......................................107
COMPONENT DESCRIPTION ..........................107
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE
SENSOR ............................................................108
COMPONENT INSPECTION .............................109
Sunload Sensor Circuit .........................................110
COMPONENT DESCRIPTION ..........................110
SUNLOAD INPUT PROCESS ...........................110
DIAGNOSTIC PROCEDURE FOR SUNLOAD
SENSOR ............................................................110

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Revision: 2004 November 2004 FX35/FX45COMPONENT INSPECTION ............................. 112
Intake Sensor Circuit ............................................. 113
COMPONENT DESCRIPTION .......................... 113
DIAGNOSTIC PROCEDURE FOR INTAKE SEN-
SOR ................................................................... 113
COMPONENT INSPECTION ............................. 114
CONTROLLER ........................................................115
Removal and Installation of A/C and AV Switch .... 115
REMOVAL .......................................................... 115
INSTALLATION .................................................. 115
AUTO AMP ..............................................................116
Removal and Installation of Unified Meter and A/C
Amp. ...................................................................... 116
REMOVAL .......................................................... 116
INSTALLATION .................................................. 116
AMBIENT SENSOR .................................................117
Removal and Installation ....................................... 117
REMOVAL .......................................................... 117
INSTALLATION .................................................. 117
IN-VEHICLE SENSOR .............................................118
Removal and Installation ....................................... 118
REMOVAL .......................................................... 118
INSTALLATION .................................................. 118
SUNLOAD SENSOR ...............................................119
Removal and Installation ....................................... 119
REMOVAL .......................................................... 119
INSTALLATION .................................................. 119
INTAKE SENSOR ................................................... 120
Removal and Installation ...................................... 120
REMOVAL ......................................................... 120
INSTALLATION ................................................. 120
BLOWER UNIT ....................................................... 121
Removal and Installation ...................................... 121
REMOVAL ......................................................... 121
INSTALLATION ................................................. 121
Disassembly and Assembly ................................. 122
BLOWER MOTOR .................................................. 123
Removal and Installation ...................................... 123
REMOVAL ......................................................... 123
INSTALLATION ................................................. 123
INTAKE DOOR MOTOR ......................................... 124
Removal and Installation ...................................... 124
REMOVAL ......................................................... 124
INSTALLATION ................................................. 124
IN-CABIN MICROFILTER ....................................... 125
Removal and Installation ...................................... 125
FUNCTION ........................................................ 125
REPLACEMENT TIMING .................................. 125
REPLACEMENT PROCEDURES ..................... 125
HEATER & COOLING UNIT ASSEMBLY .............. 126
Removal and Installation ...................................... 126
REMOVAL ......................................................... 126
INSTALLATION ................................................. 127
Disassembly and Assembly ................................. 128
MODE DOOR MOTOR ........................................... 130
Removal and Installation ...................................... 130
REMOVAL ......................................................... 130
INSTALLATION ................................................. 130AIR MIX DOOR MOTOR .........................................131
Removal and Installation ......................................131
REMOVAL .........................................................131
INSTALLATION .................................................131
HEATER CORE .......................................................132
Removal and Installation ......................................132
REMOVAL .........................................................132
INSTALLATION .................................................132
DUCTS AND GRILLES ...........................................133
Removal and Installation ......................................133
REMOVAL .........................................................133
INSTALLATION .................................................136
REFRIGERANT LINES ...........................................137
HFC-134a (R-134a) Service Procedure ...............137
SETTING OF SERVICE TOOLS AND EQUIP-
MENT ................................................................137
Components .........................................................139
VK45DE .............................................................139
VQ35DE ............................................................140
Removal and Installation of Compressor ..............140
REMOVAL .........................................................140
INSTALLATION .................................................142
Removal and Installation of Compressor Clutch ..143
REMOVAL .........................................................143
INSTALLATION .................................................145
Removal and Installation of Low-pressure Flexible
Hose .....................................................................147
REMOVAL .........................................................147
INSTALLATION .................................................148
Removal and Installation of High-pressure Flexible
Hose .....................................................................148
REMOVAL .........................................................148
INSTALLATION .................................................149
Removal and Installation of Low-pressure Pipe 1
(Engine Compartment) .........................................149
REMOVAL .........................................................149
INSTALLATION .................................................150
Removal and Installation of High-pressure Pipe 1
and 2 (Engine Compartment) ...............................150
REMOVAL .........................................................150
INSTALLATION .................................................151
Removal and Installation of Low-pressure Pipe 2
and High-pressure Pipe 3 .....................................151
REMOVAL .........................................................151
INSTALLATION .................................................152
Removal and Installation of Liquid Tank ...............153
REMOVAL .........................................................153
INSTALLATION .................................................153
Removal and Installation of Condenser ................154
REMOVAL .........................................................154
INSTALLATION .................................................154
Removal and Installation of Refrigerant Pressure
Sensor ..................................................................155
REMOVAL .........................................................155
INSTALLATION .................................................155
Removal and Installation of Evaporator ................155
REMOVAL .........................................................155
INSTALLATION .................................................155
Removal and Installation of Expansion Valve .......156

ATC-8
PRECAUTIONS
Revision: 2004 November 2004 FX35/FX45
Precautions for Refrigerant ConnectionAJS0013Y
A new type refrigerant connection has been introduced to all refrigerant lines except the following location.

Expansion valve to evaporator

Refrigerant pressure sensor to condenser
ABOUT ONE-TOUCH JOINT
Description

One-touch joints are pipe joints which do not require tools during piping connection.

Unlike conventional connection methods using union nuts and flanges, controlling tightening torque at
connection point is not necessary.

When removing a pipe joint, use a disconnector.
COMPONENT PARTS
FUNCTIONS OF COMPONENT PARTS
NOTE:

Garter spring cannot be removed from cage of male-side piping.

Indicator ring remains near piping connection point, however, this is not a malfunction. (This is to check
piping connection during factory assembly.)
Pipe (Male side)
Retains O-rings.

Retains garter spring in cage.
Garter spring Anchors female side piping.
Indicator ringWhen connection is made properly, this is ejected from male-side piping. (This part is no longer neces-
sary after connection.)
O-ring Seals connection point. (Not reusable)
Pipe (Female side)

Seals connection by compressing O-rings.

Anchors piping connection using flare and garter spring.
RJIA0970E

ATC-12
PRECAUTIONS
Revision: 2004 November 2004 FX35/FX45
CAUTION:
The new and former refrigerant connections use different O-ring configurations. Do not 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 position as it is when mounted on the car.
Malfunction 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 as the final stage of the opera-
tion. Do not remove the seal caps of pipes and other components until just before required for
connection.

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.
Lubricant name: Nissan A/C System Oil Type S
Part number: KLH00-PAGS0

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 you hear it click, 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
NewLow-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 pipeInlet
92471 N82101
8
Outlet 1
FormerRefrigerant pressure sensor to condenser J2476 89956 1 10
Expansion valve to evaporatorInlet 92475 71L00 1 12
Outlet 92475 72L00 1 16

REFRIGERATION SYSTEM
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Revision: 2004 November 2004 FX35/FX45
REFRIGERATION SYSTEMPFP:KA990
Refrigerant CycleAJS00146
REFRIGERANT FLOW
The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the evaporator, and back to the compressor. The refrigerant evaporation through the evaporator coil is
controlled by an externally equalized expansion valve, located inside the evaporator case.
FREEZE PROTECTION
Under usual operating conditions, when the A/C is switched on, the compressor runs continuously, and the
evaporator pressure, and therefore, temperature is controlled by the compressor to prevent freeze up.
Refrigerant System ProtectionAJS00147
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 (28 kg/cm
2 , 398 psi), or below about 134 kPa
(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 (38 kg/cm
2
, 540 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the
atmosphere.
RJIA0849E

ATC-30
AIR CONDITIONER CONTROL
Revision: 2004 November 2004 FX35/FX45
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 the 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, mode door motor and 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 are compared by the LCUs in each motor with the existing decision and opening
angles. Subsequently, HOT/COLD, DEFROST/VENT or FRESH/RECIRCULATION operation is selected. The
new selection data is returned to the unified meter and A/C amp.
SJIA0262E
RJIA1747E

AIR CONDITIONER CONTROL
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Revision: 2004 November 2004 FX35/FX45
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-DIAGNOSTIC SYSTEM
The self-diagnostic 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: 2004 November 2004 FX35/FX45
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
RJIA1958E
RJIA1959E