control INFINITI M35 2007 Factory Service Manual

AT-364
ASSEMBLY
Revision: 2007 April2007 M35/M45
8. Make sure that brake band does not close turbine revolution
sensor hole.
9. Install control valve with TCM.
a. Connect TCM connector and park/neutral position switch con-
nector.
b. Install A/T assembly harness connector to control valve with
TCM.
c. Connect TCM connectors.
SCIA5034E
SCIA5449E
SCIA5450E
SCIA5447E

ASSEMBLY
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d. Install O-ring to A/T assembly harness connector.
CAUTION:

Do not reuse O-ring.

Apply ATF to O-ring.
e. Install A/T fluid temperature sensor 2 to bracket.
f. Install A/T fluid temperature sensor 2 (with bracket) in control
valve with TCM. Tighten A/T fluid temperature sensor 2 bolt to
the specified torque. Refer to AT- 2 8 1 , "
Components" .
CAUTION:
Adjust bolt hole of bracket to bolt hole of control valve.
g. Install control valve with TCM in transmission case.
CAUTION:

Make sure that turbine revolution sensor securely installs
turbine revolution sensor hole.

Hang down revolution sensor harness toward outside so
as not to disturb installation of control valve with TCM.

Adjust A/T assembly harness connector of control valve
with TCM to terminal hole of transmission case.

Assemble it so that manual valve cutout is engaged with
manual plate projection.
SCIA5155E
SCIA5264E
SCIA5301E
SCIA5034E
SCIA5035E

AT-366
ASSEMBLY
Revision: 2007 April2007 M35/M45
h. Install bolts A, B and C to control valve with TCM.
i. Tighten bolt 1, 2 and 3 temporarily to prevent dislocation. After
that tighten them in order (1 → 2 → 3), and then tighten other
bolts. Tighten control valve bolts to the TCM with specified
torque. Refer to AT- 2 8 1 , "
Components" .
10. Connect A/T fluid temperature sensor 2 connector.
11. Securely fasten terminal cord assembly and A/T fluid tempera-
ture sensor 2 harness with terminal clips.
12. Connect revolution sensor connector.
Bolt symbol Length mm (in) Number of bolts
A 42 (1.65) 5
B 55 (2.17) 6
C 40 (1.57) 1
SCIA5025E
SCIA5037E
SCIA5023E
SCIA5446E
SCIA7524E

ATC-1
AUTOMATIC AIR CONDITIONER
J AIR CONDITIONER
CONTENTS
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Revision: 2007 April2007 M35/M45
AUTOMATIC AIR CONDITIONER
PRECAUTIONS .......................................................... 5
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 5
Precautions Necessary for Steering Wheel Rotation
After Battery Disconnect .......................................... 5
OPERATION PROCEDURE ................................. 5
Precautions for Procedures without Cowl Top Cover ..... 6
Precautions for Working with HFC-134a (R-134a) ..... 6
CONTAMINATED REFRIGERANT ....................... 7
General Refrigerant Precautions .............................. 7
Precautions for Refrigerant Connection ................... 7
ABOUT ONE-TOUCH JOINT ................................ 7
FEATURES OF NEW TYPE REFRIGERANT
CONNECTION .................................................... 10
O-RING AND REFRIGERANT CONNECTION ... 10
Precautions for Servicing Compressor ................... 12
Precautions for Service Equipment ........................ 13
RECOVERY/RECYCLING EQUIPMENT ............ 13
ELECTRICAL LEAK DETECTOR ....................... 13
VACUUM PUMP ................................................. 13
MANIFOLD GAUGE SET .................................... 13
SERVICE HOSES ............................................... 14
SERVICE COUPLERS ........................................ 14
REFRIGERANT WEIGHT SCALE ...................... 14
CHARGING CYLINDER ...................................... 14
Precautions for Leak Detection Dye ....................... 15
IDENTIFICATION ................................................ 15
IDENTIFICATION LABEL FOR VEHICLE ........... 15
PREPARATION ......................................................... 16
Special Service Tools ............................................. 16
HFC-134a (R-134a) Service Tools and Equipment ... 17
Commercial Service Tools ...................................... 19
REFRIGERATION SYSTEM ..................................... 20
Refrigerant Cycle ................................................... 20
REFRIGERANT FLOW ....................................... 20
FREEZE PROTECTION ..................................... 20
Refrigerant System Protection ............................... 20
REFRIGERANT PRESSURE SENSOR ............. 20
PRESSURE RELIEF VALVE ............................... 20Variable Displacement Compressor ....................... 21
GENERAL INFORMATION ................................. 21
DESCRIPTION .................................................... 22
Component Layout ................................................. 25
LUBRICANT .............................................................. 26
Maintenance of Lubricant Quantity in Compressor ... 26
LUBRICANT ........................................................ 26
LUBRICANT RETURN OPERATION .................. 26
LUBRICANT ADJUSTING PROCEDURE FOR
COMPONENTS REPLACEMENT EXCEPT
COMPRESSOR .................................................. 27
LUBRICANT ADJUSTING PROCEDURE FOR
COMPRESSOR REPLACEMENT ....................... 27
AIR CONDITIONER CONTROL ............................... 29
Description of Air Conditioner LAN Control System ... 29
System Construction .............................................. 29
OPERATION ........................................................ 30
TRANSMISSION DATA AND TRANSMISSION
ORDER ............................................................... 30
AIR MIX DOOR CONTROL (AUTOMATIC TEM-
PERATURE CONTROL) ..................................... 31
FAN SPEED CONTROL ...................................... 31
INTAKE DOOR CONTROL ................................. 31
MODE DOOR CONTROL ................................... 31
UPPER VENTILATOR DOOR CONTROL .......... 31
MAGNET CLUTCH CONTROL ........................... 32
SELF-DIAGNOSIS SYSTEM .............................. 32
Description of Control System ................................ 33
Control Operation ................................................... 33
DISPLAY SCREEN .............................................. 33
MULTIFUNCTION SWITCH ................................ 34
DISPLAY SCREEN .............................................. 34
MODE SWITCH (DRIVER SIDE) ........................ 34
MODE SWITCH (PASSENGER SIDE) ................ 34
TEMPERATURE CONTROL SWITCH (POTEN-
TIO TEMPERATURE CONTROL) (DRIVER
SIDE) ................................................................... 34
TEMPERATURE CONTROL SWITCH (POTEN-
TIO TEMPERATURE CONTROL) (PASSEN-
GER SIDE) .......................................................... 34

ATC-2Revision: 2007 April2007 M35/M45 AUTO SWITCH ................................................... 34
DEFROSTER (DEF) SWITCH ............................. 34
UPPER VENT SWITCH ...................................... 34
A/C SWITCH ....................................................... 35
FAN SWITCHES .................................................. 35
OFF SWITCH ...................................................... 35
REAR WINDOW DEFOGGER SWITCH ............. 35
INTAKE SWITCH ................................................. 35
DUAL SWITCH .................................................... 35
Control Operation (Rear Control Switch) ................ 35
AUTO SWITCH ................................................... 35
FAN SWITCH ...................................................... 35
REAR TEMPERATURE CONTROL SWITCH ..... 36
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 Function (ECM) .................................. 40
CONSULT-II BASIC OPERATION ....................... 40
DATA MONITOR .................................................. 40
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ...................................................... 40
WORK FLOW ...................................................... 40
SYMPTOM TABLE .............................................. 41
Component Parts and Harness Connector Location ... 42
ENGINE COMPARTMENT .................................. 42
PASSENGER COMPARTMENT .......................... 43
Schematic ............................................................... 44
Wiring Diagram —A/C— ......................................... 46
Auto Amp. Terminals and Reference Value ............ 54
PIN CONNECTOR TERMINAL LAYOUT ............ 54
TERMINALS AND REFERENCE VALUE FOR
UNIFIED METER AND A/C AMP. ........................ 54
Self-diagnosis Function .......................................... 56
DESCRIPTION .................................................... 56
FUNCTION CONFIRMATION PROCEDURE ...... 57
AUXILIARY MECHANISM: TEMPERATURE
SETTING TRIMMER ........................................... 63
AUXILIARY MECHANISM: FOOT POSITION
SETTING TRIMMER ........................................... 64
AUXILIARY MECHANISM: INLET PORT MEM-
ORY FUNCTION ................................................. 64
Operational Check .................................................. 65
CHECKING MEMORY FUNCTION ..................... 65
CHECKING BLOWER ......................................... 65
CHECKING DISCHARGE AIR (MODE SWITCH
AND DEF SWITCH) ............................................ 65
CHECKING DISCHARGE AIR (UPPER VENT
SWITCH) ............................................................. 66
CHECKING INTAKE AIR ..................................... 66
CHECKING TEMPERATURE DECREASE ......... 66
CHECKING TEMPERATURE INCREASE .......... 66
CHECKING A/C SWITCH ................................... 66
CHECKING AUTO MODE ................................... 66
Power Supply and Ground Circuit for Auto Amp. ... 67
INSPECTION FLOW ........................................... 67
COMPONENT DESCRIPTION ............................ 68DIAGNOSIS PROCEDURE FOR A/C SYSTEM ... 68
Rear Control Switch Circuit ..................................... 70
DIAGNOSIS PROCEDURE FOR REAR CON-
TROL SWITCH .................................................... 70
LAN System Circuit ................................................. 71
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT ... 71
Mode Door Motor Circuit ......................................... 76
INSPECTION FLOW ............................................ 76
SYSTEM DESCRIPTION ..................................... 77
COMPONENT DESCRIPTION ............................ 78
DIAGNOSIS PROCEDURE FOR MODE DOOR
MOTOR ................................................................ 78
Upper Ventilator Door Motor Circuit ........................ 79
INSPECTION FLOW ............................................ 79
SYSTEM DESCRIPTION ..................................... 80
COMPONENT DESCRIPTION ............................ 81
DIAGNOSIS PROCEDURE FOR UPPER VEN-
TILATOR DOOR MOTOR .................................... 81
Air Mix Door Motor Circuit ....................................... 82
INSPECTION FLOW ............................................ 82
SYSTEM DESCRIPTION ..................................... 83
COMPONENT DESCRIPTION ............................ 84
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR
MOTOR ................................................................ 84
Air Mix Door Motor PBR Circuit .............................. 84
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR
MOTOR PBR ....................................................... 84
Intake Door Motor Circuit ........................................ 85
INSPECTION FLOW ............................................ 85
SYSTEM DESCRIPTION ..................................... 86
COMPONENT DESCRIPTION ............................ 87
DIAGNOSIS PROCEDURE FOR INTAKE DOOR
MOTOR ................................................................ 87
Blower Motor Circuit ................................................ 88
INSPECTION FLOW ............................................ 88
SYSTEM DESCRIPTION ..................................... 89
COMPONENT DESCRIPTION ............................ 90
DIAGNOSIS PROCEDURE FOR BLOWER
MOTOR ................................................................ 90
COMPONENT INSPECTION ............................... 92
Magnet Clutch Circuit .............................................. 93
INSPECTION FLOW ............................................ 93
SYSTEM DESCRIPTION ..................................... 94
DIAGNOSIS PROCEDURE FOR MAGNET
CLUTCH .............................................................. 94
COMPONENT INSPECTION ............................... 97
Insufficient Cooling .................................................. 98
INSPECTION FLOW ............................................ 98
PERFORMANCE TEST DIAGNOSIS ................100
PERFORMANCE CHART ..................................102
TROUBLE DIAGNOSIS FOR UNUSUAL PRES-
SURE .................................................................104
DIAGNOSIS PROCEDURE FOR INSUFFI-
CIENT COOLING ...............................................106
Insufficient Heating ...............................................108
INSPECTION FLOW ..........................................108
Noise .....................................................................109
INSPECTION FLOW ..........................................109
Self-diagnosis .......................................................110

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Revision: 2007 April2007 M35/M45 INSPECTION FLOW .......................................... 110
Memory Function ................................................. . 111
INSPECTION FLOW ......................................... . 111
Ambient Sensor Circuit ......................................... 112
COMPONENT DESCRIPTION .......................... 112
AMBIENT TEMPERATURE INPUT PROCESS .. 112
DIAGNOSIS PROCEDURE FOR AMBIENT
SENSOR ............................................................ 112
COMPONENT INSPECTION ............................. 114
In-vehicle Sensor Circuit ....................................... 115
COMPONENT DESCRIPTION .......................... 115
DIAGNOSIS PROCEDURE FOR IN-VEHICLE
SENSOR ............................................................ 116
COMPONENT INSPECTION ............................. 117
Sunload Sensor Circuit ......................................... 118
COMPONENT DESCRIPTION .......................... 118
SUNLOAD INPUT PROCESS ........................... 118
DIAGNOSIS PROCEDURE FOR SUNLOAD
SENSOR ............................................................ 118
COMPONENT INSPECTION ............................ 120
Intake Sensor Circuit ............................................ 121
COMPONENT DESCRIPTION ......................... 121
DIAGNOSIS PROCEDURE FOR INTAKE SEN-
SOR .................................................................. 121
COMPONENT INSPECTION ............................ 122
CONTROLLER ....................................................... 123
Removal and Installation of Multifunction Switch . 123
REMOVAL ......................................................... 123
INSTALLATION ................................................. 123
AUTO AMP ............................................................. 124
Removal and Installation of Unified Meter and A/C
Auto Amp. ............................................................ 124
REMOVAL ......................................................... 124
INSTALLATION ................................................. 124
AMBIENT SENSOR ................................................ 125
Removal and Installation ...................................... 125
REMOVAL ......................................................... 125
INSTALLATION ................................................. 125
IN-VEHICLE SENSOR ............................................ 126
Removal and Installation ...................................... 126
REMOVAL ......................................................... 126
INSTALLATION ................................................. 126
SUNLOAD SENSOR .............................................. 127
Removal and Installation ...................................... 127
REMOVAL ......................................................... 127
INSTALLATION ................................................. 127
INTAKE SENSOR ................................................... 128
Removal and Installation ...................................... 128
REMOVAL ......................................................... 128
INSTALLATION ................................................. 128
BLOWER UNIT ....................................................... 129
Removal and Installation ...................................... 129
REMOVAL ......................................................... 129
INSTALLATION ................................................. 129
Disassembly and Assembly ................................. 130
BLOWER MOTOR .................................................. 131
Removal and Installation ...................................... 131
REMOVAL ......................................................... 131
INSTALLATION ................................................. 131INTAKE DOOR MOTOR .........................................132
Removal and Installation ......................................132
REMOVAL .........................................................132
INSTALLATION .................................................132
IN-CABIN MICROFILTER .......................................133
Removal and Installation ......................................133
FUNCTION ........................................................133
REPLACEMENT TIMING ..................................133
REPLACEMENT PROCEDURES .....................133
HEATER & COOLING UNIT ASSEMBLY ...............134
Removal and Installation ......................................134
REMOVAL .........................................................134
INSTALLATION .................................................135
Disassembly and Assembly ..................................137
MODE DOOR MOTOR ............................................139
Removal and Installation ......................................139
REMOVAL .........................................................139
INSTALLATION .................................................139
AIR MIX DOOR MOTOR .........................................140
Removal and Installation ......................................140
REMOVAL .........................................................140
INSTALLATION .................................................140
UPPER VENTILATOR DOOR MOTOR ..................141
Removal and Installation ......................................141
REMOVAL .........................................................141
INSTALLATION .................................................141
HEATER CORE .......................................................142
Removal and Installation ......................................142
REMOVAL .........................................................142
INSTALLATION .................................................142
DUCTS AND GRILLES ...........................................143
Removal and Installation ......................................143
COMPONENT LAYOUT ....................................143
REMOVAL .........................................................145
INSTALLATION .................................................149
REFRIGERANT LINES ...........................................150
HFC-134a (R-134a) Service Procedure ...............150
SETTING OF SERVICE TOOLS AND EQUIP-
MENT ................................................................150
Components .........................................................152
VQ35DE ............................................................152
VK45DE .............................................................153
Removal and Installation of Compressor ..............153
REMOVAL .........................................................153
INSTALLATION .................................................156
Check Disc to Pulley Clearance ...........................156
Removal and Installation of Low-pressure Flexible
Hose and Pipe ......................................................157
REMOVAL .........................................................157
INSTALLATION .................................................157
Removal and Installation of High-pressure Flexible
Hose .....................................................................158
REMOVAL .........................................................158
INSTALLATION .................................................159
Removal and Installation of High-pressure Pipe 1
(Engine Compartment) .........................................159
REMOVAL .........................................................159
INSTALLATION .................................................160
Removal and Installation of Low-pressure Pipe 1

PRECAUTIONS
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PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
NJS000FN
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions Necessary for Steering Wheel Rotation After Battery DisconnectNJS000FO
NOTE:

This Procedure is applied only to models with Intelligent Key system and NVIS/IVIS (NISSAN/INFINITI
VEHICLE IMMOBILIZER SYSTEM - NATS).

Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK″ position.

Always use CONSULT-II to perform self-diagnosis as a part of each function inspection after finishing
work. If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NVIS/IVIS, an electrically controlled steering lock
mechanism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery power is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables.
NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
5. When the repair work is completed, return the ignition switch to the ″LOCK″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of all control units using CONSULT-II.

PRECAUTIONS
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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
WARNING:

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 52°C (126°F).

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.

ATC-14
PRECAUTIONS
Revision: 2007 April2007 M35/M45
SERVICE HOSES
Be certain that the service hoses display the markings described
(colored hose with black stripe). All hoses must include positive shut-
off devices (either manual or automatic) near the end of the hoses
opposite to the manifold gauge.
SERVICE COUPLERS
Never attempt to connect HFC-134a (R-134a) service couplers to a
CFC-12 (R-12) A/C system. The HFC-134a (R-134a) couplers will
not properly connect to the CFC-12 (R-12) system. However, if an
improper connection is attempted, discharging and contamination
may occur.
REFRIGERANT WEIGHT SCALE
Verify that no refrigerant other than HFC-134a (R-134a) and speci-
fied lubricants have been used with the scale. If the scale controls
refrigerant flow electronically, the hose fitting must be 1/2″-16
ACME.
CHARGING CYLINDER
Using a charging cylinder is not recommended. Refrigerant may be vented into air from cylinder’s top valve
when filling the cylinder with refrigerant. Also, the accuracy of the cylinder is generally less than that of an
electrical scale or of quality recycle/recharge equipment.
RHA272D
Shut-off valve rotation A/C service valve
Clockwise Open
Counterclockwise Close
RHA273D
RHA274D

ATC-20
REFRIGERATION SYSTEM
Revision: 2007 April2007 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