lan s INFINITI FX35 2004 Owner's Manual
Page 431 of 4449
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
Page 437 of 4449
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
Page 451 of 4449
ATC-22
REFRIGERATION SYSTEM
Revision: 2004 November 2004 FX35/FX45
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.
Page 453 of 4449
ATC-24
REFRIGERATION SYSTEM
Revision: 2004 November 2004 FX35/FX45
Operation
1. Operation Control Valve
–By changing high-pressure valve lift amount, built-in compressor control valve executes the following:
Controls high-pressure valve discharge amount.
Changes crankcase pressure in compressor.
Changes angle of wobble (swash) plate.
–Amount of high-pressure valve loft is determined by factors below.
Low-pressure applied to diaphragm
Spring load of set spring
Balance of magnetic force generated in magnet coil
–Electronic control valve (ECV) magnet coil receives electric signal (duty control) from unified meter and A/
C amp. (Auto amp.) Then, magnetic force generated by electric current is changed to control high-pres-
sure valve lift amount.
2. Maximum Cooling
High-pressure valve is closed by magnetic force generated by electric signal sent from unified meter and
A/C amp. At this time, cylinder moves full stroke due to pressure balance between inside crankcase (Pc)
and suction line (Ps).
Under this condition, the wobble (swash) plate is set to the maximum stroke position.
3. Capacity Control
When no electric signal is sent from unified meter and A/C amp. (current: OFF), high-pressure valve is
opened by spring force.
Since suction pressure is low, it makes the suction port close and the discharge port open. Thus, crank-
case pressure becomes high as high-pressure enters the crankcase.
–The force acts around the journal pin near the wobble (swash) plate, and is generated by the pressure dif-
ference before and behind the piston.
–The drive lug and journal pin are located where the piston generates the highest pressure. Piston pres-
sure is between suction pressure Ps and discharge pressure Pd, which is near suction pressure Ps. If
crankcase pressure Pc rises due to capacity control, the force around the journal pin makes the wobble
(swash) plate angle decrease and also the piston stroke decrease. In other words, crankcase pressure
RJIA0851E
Page 459 of 4449
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
Page 461 of 4449
ATC-32
AIR CONDITIONER CONTROL
Revision: 2004 November 2004 FX35/FX45
Stop Signal:
At the end of each transmission, a stop operation, in-operation, or internal error 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 temperature setting, ambient temperature, in-vehicle temperature,
intake temperature, amount of sunload and air mix door position.
When 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.
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Page 468 of 4449
AIR CONDITIONER CONTROL
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AT C
Revision: 2004 November 2004 FX35/FX45
CAN Communication System DescriptionAJS0014H
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to LAN-6,
"CAN Communication Unit" .
Page 471 of 4449
ATC-42
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
How to Perform Trouble Diagnosis for Quick and Accurate RepairAJS0014K
WORK FLOW
SYMPTOM TABLE
*1ATC-61, "Operational Check"
SHA900E
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System.AT C - 6 3 , "
Power
Supply and Ground
Circuit for Auto
Amp."
A/C system cannot be controlled.Go to Integrated Display System.
Go to Navigation System.AV-78, "
Trouble
Diagnosis Chart by
Symptom" (Without
navigation system)
or AV-84, "
A/C and
AV Switch Does Not
Operate" (With nav-
igation system)
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. (LAN)AT C - 7 0 , "
Mode
Door Motor Circuit"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-73, "
Air Mix
Door Motor Circuit"Air mix door motor does not operate nor-
mally.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. (LAN)ATC-76, "
Intake
Door Motor Circuit"Intake door motor does not operate nor-
mally.
Blower motor operation is malfunctioning.
Go to Trouble Diagnosis Procedure for Blower Motor.ATC-79, "
Blower
Motor Circuit"Blower motor operation is malfunctioning
under out of starting fan speed control.
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch.ATC-84, "
Magnet
Clutch Circuit"
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling.AT C - 9 1 , "
Insufficient
Cooling"
Go to Diagnostic Procedure for Insufficient Cooling.AT C - 9 8 , "
DIAG-
NOSTIC PROCE-
DURE FOR
INSUFFICIENT
COOLING"
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.ATC-100, "Insuffi-
cient Heating"
Noise Go to Trouble Diagnosis Procedure for Noise.ATC-101, "Noise"
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis.ATC-102, "Self-
diagnosis"
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.ATC-103, "Memory
Function"
Page 480 of 4449
TROUBLE DIAGNOSIS
ATC-51
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Revision: 2004 November 2004 FX35/FX45
Auto Amp. Terminals and Reference ValueAJS0014O
Measure voltage between each terminal and ground by following ter-
minals and reference value for unified meter and A/C amp.
PIN CONNECTOR TERMINAL LAYOUT
TERMINALS AND REFERENCE VALUE FOR UNIFIED METER AND A/C AMP.
RJIA1965E
RJIA1966E
Terminal
No.Wire
colorItemIgnition
switchConditionVoltage
(V)
1 L CAN H - - -
11 R C A N L - - -
21 R/W Power supply for BATT OFF - Battery voltage
22 G/R Power supply for IGN ON - Battery voltage
29 B Ground (Power) ON - Approx. 0
30 B Ground ON - Approx. 0
35 LG/R Power supply for ACC ON - Battery voltage
39 Y Ambient sensor - - -
40 BR/W In-vehicle sensor - - -
41 P Intake sensor - - -
42 R/Y Compressor ON signal ONA/C switch: ON Approx. 0
A/C switch: OFF Approx. 5
43 G/B A/C LAN signal ON -
45 PU/WECV (Electric Control Valve)
signalON -
HAK0652D
RJIA1606E
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TROUBLE DIAGNOSIS
ATC-57
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Revision: 2004 November 2004 FX35/FX45
12. CHECK CAN COMMUNICATION ERROR
1. Press (REC) switch.
2. CAN communication error between unified meter and A/C amp.
and DISPLAY UNIT or DISPLAY C/U is detected.
OK or NG
OK >> 1. Turn ignition switch OFF or AUTO switch ON.
2. INSPECTION END
NG >> Go to CAN communication. Refer to BCS-14, "
CAN
Communication Inspection Using CONSULT-II (Self-
Diagnosis)" .
Unified meter and A/C amp. - DISPLAY UNIT
Unified meter and A/C amp. - DISPLAY C/U
13. CHECK MALFUNCTIONING SENSOR
Refer to the following chart for malfunctioning code No.
(If two or more sensors malfunction, corresponding code Nos. blink respectively twice.)
*1: Perform self-diagnosis STEP-2 under sunshine.
When performing indoors, aim a light (more than 60W) at sunload sensor, otherwise code No. 25 will indicate
despite that sunload sensor is functioning properly.
*2: ATC-104, "
DIAGNOSTIC PROCEDURE FOR AMBIENT SENSOR" .
*3: ATC-108, "
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE SENSOR" .
*4: AT C - 11 3 , "
DIAGNOSTIC PROCEDURE FOR INTAKE SENSOR" .
*5: AT C - 11 0 , "
DIAGNOSTIC PROCEDURE FOR SUNLOAD SENSOR" .
*6: AT C - 6 6 , "
DIAGNOSTIC PROCEDURE FOR LAN CIRCUIT" .
>> INSPECTION END
RJIA1969E
Code No. Malfunctioning sensor (Including circuits) Reference page
21 / −21 Ambient sensor *2
22 / −22 In-vehicle sensor *3
24 / −24 Intake sensor *4
25 / −25 Sunload sensor *1 *5
26 / −26 Air mix door motor PBR (Driver side)
*6
27 / −27 Air mix door motor PBR (Passenger side)
RJIA0227E