ATC-4Revision: 2006 January2006 M35/M45 and High-Pressure Pipe 2 ....................................162
REMOVAL ........................................................
.162
INSTALLATION ..................................................163
Removal and Installation of Liquid Tank ...............164
DISASSEMBLY AND ASSEMBLY ....................164
REMOVAL ........................................................
.164
INSTALLATION ..................................................165
Removal and Installation of Condenser ................165
REMOVAL ........................................................
.165
INSTALLATION ..................................................167
Removal and Installation of Refrigerant Pressure
Sensor ..................................................................167
REMOVAL ........................................................
.167
INSTALLATION ..................................................167
Removal and Installation of Evaporator ................168
REMOVAL ........................................................
.168
INSTALLATION ..................................................168Removal and Installation of Expansion Valve .......169
REMOVAL ..........................................................169
INSTALLATION ..................................................169
Checking for Refrigerant Leaks ............................170
Checking System for Leaks Using the Fluorescent
Leak Detector ........................................................170
Dye Injection .........................................................170
Electrical Refrigerant Leak Detector .....................171
PRECAUTIONS FOR HANDLING LEAK
DETECTOR .......................................................171
CHECKING PROCEDURE ................................172
SERVICE DATA AND SPECIFICATIONS (SDS) ....174
Compressor ..........................................................174
Lubricant ...............................................................174
Refrigerant ............................................................174
Engine Idling Speed ..............................................174
Belt Tension ..........................................................174
PRECAUTIONS
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Revision: 2006 January2006 M35/M45
CONTAMINATED REFRIGERANT
If a refrigerant other than pure HFC-134a (R-134a) is identified in a vehicle, take appropriate steps
shown below:
Explain to the customer that environmental regulations prohibit the release of contaminated refrigerant
into the atmosphere.
Explain that recovery of the contaminated refrigerant could damage service equipment and refrigerant
supply.
Suggest the customer return the vehicle to the location of previous service where the contamination may
have occurred.
In case of repairing, recover the refrigerant using only dedicated equipment and containers. Never
recover contaminated refrigerant into the existing service equipment. If the facility does not have
dedicated recovery equipment, contact a local refrigerant product retailer for available service. This refrig-
erant must be disposed of in accordance with all federal and local regulations. In addition, replacement of
all refrigerant system components on the vehicle is recommended.
If the vehicle is within the warranty period, the air conditioner warranty is void. Please contact Nissan Cus-
tomer Affairs for further assistance.
General Refrigerant PrecautionsNJS000FR
WAR NING :
Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and
throat. Remove HFC-134a (R-134a) from the A/C system, using certified service equipment meet-
ing requirements of SAE J-2210 [HFC-134a (R-134a) recycling equipment], or J-2209 [HFC-134a (R-
134a) recovery equipment]. If accidental system discharge occurs, ventilate work area before
resuming service. Additional health and safety information may be obtained from refrigerant and
lubricant manufacturers.
Never release refrigerant into the air. Use approved recovery/recycling equipment to capture the
refrigerant every time an air conditioning system is discharged.
Always wear eye and hand protection (goggles and gloves) when working with any refrigerant or
air conditioning system.
Never store or heat refrigerant containers above 52C (126F).
Never heat a refrigerant container with an open flame; if container warming is required, place the
bottom of the container in a warm pail of water.
Never intentionally drop, puncture, or incinerate refrigerant containers.
Keep refrigerant away from open flames: poisonous gas will be produced if refrigerant burns.
Refrigerant will displace oxygen, therefore be certain to work in well ventilated areas to prevent
suffocation.
Never pressure test or leak test HFC-134a (R-134a) service equipment and/or vehicle air condition-
ing systems with compressed air during repair. Some mixtures of air and HFC-134a (R-134a) have
been shown to be combustible at elevated pressures. These mixtures, if ignited, may cause injury
or property damage. Additional health and safety information may be obtained from refrigerant
manufacturers.
Precautions for Refrigerant ConnectionNJS000FS
A new type refrigerant connection has been introduced to all refrigerant lines except the following location.
Expansion valve to evaporator
Refrigerant pressure sensor to liquid tank
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.
PRECAUTIONS
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Revision: 2006 January2006 M35/M45
VK45DE
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 may leak at the con-
nection.
O-Ring Part Numbers and Specifications
RJIA4011E
Connection type Piping connection point Part number QTY O-ring size
NewLow-pressure flexible hose to low-pressure pipe 1 (One-
touch joint)92473 N8221 2 16
High-pressure pipe 1 to high-pressure pipe 2 (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 28
Low-pressure pipe to low-pressure flexible hose (VK45DE) 92474 N8210 1 19
Low-pressure pipe 1 to expansion valve 92473 N8210 1 16
High-pressure pipe 2 to expansion valve 92471 N8210 1 8
Compressor to low-pressure flexible hose (VQ35DE)
92474 N8210 1 19
Compressor to low-pressure pipe (VK45DE)
Compressor to high-pressure flexible hose 92472 N8210 1 12
Liquid tank to condenser pipeInlet
92471 N82101
8
Outlet 1
FormerRefrigerant pressure sensor to liquid tank J2476 89956 1 10
Expansion valve to evaporatorInlet 92475 71L00 1 12
Outlet 92475 72L00 1 16
ATC-20
REFRIGERATION SYSTEM
Revision: 2006 January2006 M35/M45
REFRIGERATION SYSTEMPFP:KA990
Refrigerant CycleNJS000FZ
REFRIGERANT FLOW
The refrigerant flows from 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 ProtectionNJS000G0
REFRIGERANT PRESSURE SENSOR
The refrigerant system is protected against excessively high- or low-pressures by the refrigerant pressure sen-
sor, located on the liquid tank. If the system pressure rises above, or falls below the specifications, the refriger-
ant 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 3,119 kPa (31.8 kg/cm
2 , 452 psi), or below about 118
kPa (1.2 kg/cm
2 , 17 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 3,628 kPa (37 kg/cm
2
, 526 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into the
atmosphere.
RJIA1552E
AIR CONDITIONER CONTROL
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AIR CONDITIONER CONTROLPFP:27500
Description of Air Conditioner LAN Control SystemNJS000G4
The LAN (Local Area Network) system consists of unified meter and A/C amp., mode door motors, air mix
door motors, upper ventilator door motor and intake door motor.
A configuration of these components is shown in the figure below.
System ConstructionNJS000G5
A small network is constructed between the unified meter and A/C amp., mode door motors, air mix door
motors, upper ventilator 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 mode door motors, the air mix door motors, the
upper ventilator 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)
RJIA4016E
RJIA4017E
ATC-30
AIR CONDITIONER CONTROL
Revision: 2006 January2006 M35/M45
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, upper ventilator door and intake door opening angle data to the mode door
motor LCU, air mix door motor LCU, upper ventilator door motor LCU and intake door motor LCU.
The mode door motor, air mix door motors, upper ventilator 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 door motor with
the existing decision and opening angles. Subsequently, HOT/COLD, DEF/VENT, OPEN/SHUT and FRE/REC
operation is selected. The new selection data is returned to the unified meter and A/C amp.
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 is 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
mode door motor, air mix door motor, upper ventilator 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:
In this procedure, transmitted and received data is checked for errors. Error data are then compiled. The error
check prevents corrupted data from being used by the mode door motor, the air mix door motor, the upper
ventilator 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
RJIA4018E
ATC-32
AIR CONDITIONER CONTROL
Revision: 2006 January2006 M35/M45
MAGNET CLUTCH CONTROL
When A/C switch, AUTO switch or DEF switch is pressed, unified meter and A/C amp. transmits compressor
ON signal to ECM, via CAN communication.
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.
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 ECM via CAN communication line.
ECM sends compressor feedback signal to unified meter and A/C amp., then, uses input compressor feed-
back 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 malfunc-
tions.
RJIA4020E
AIR CONDITIONER CONTROL
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Description of Control SystemNJS000G6
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 OperationNJS000G7
DISPLAY SCREEN
RJIA4021E
RJIA4022E