2007 INFINITI M35 cooling

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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

ATC-22
REFRIGERATION SYSTEM
Revision: 2007 April2007 M35/M45
DESCRIPTION
General
The variable compressor is a swash plate type that changes piston stroke in response to the required cooling
capacity.
The tilt of the swash plate allows the piston’s stroke to change so that refrigerant discharge continuously
change from approx. 0 to 171 cm
3 (0 to 10.4 cu in).
RJIA4209E

REFRIGERATION SYSTEM
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Revision: 2007 April2007 M35/M45
Operation
1. Control Valve
–By changing high-pressure valve lift amount, built-in electronic control valve executes the following:
 Controls high-pressure valve discharge amount.
 Changes crankcase pressure in compressor.
 Changes angle of swash plate.
–Amount of high-pressure valve lift 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. Then, magnetic force generated by electric current is changed to control high-pressure 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 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 link near the swash plate, and is generated by the pressure difference before
and behind the piston.
–The thrust flange and link are located where the piston generates the highest pressure. Piston pressure is
between suction pressure Ps and discharge pressure Pd, which is close to suction pressure Ps. If crank-
case pressure Pc rises due to capacity control, the force around the link makes the swash plate angle
decrease and also the piston stroke decrease. In other words, crankcase pressure increase triggers pres-
SJIA0547E

ATC-26
LUBRICANT
Revision: 2007 April2007 M35/M45
LUBRICANTPFP:KLG00
Maintenance of Lubricant Quantity in CompressorNJS000G3
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 the engine, and set to 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 the engine.
>> GO TO 3.
3. CHECK REPLACEMENT PART
Should the compressor be replaced?
YES >> GO TO AT C - 2 7 , "LUBRICANT ADJUSTING PROCEDURE FOR COMPRESSOR REPLACE-
MENT" .
NO >> GO TO AT C - 2 7 , "
LUBRICANT ADJUSTING PROCEDURE FOR COMPONENTS REPLACE-
MENT EXCEPT COMPRESSOR" . Name : Nissan A/C System Oil Type S

TROUBLE DIAGNOSIS
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Revision: 2007 April2007 M35/M45
SYMPTOM TABLE
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System.ATC-67, "
Power
Supply and Ground
Circuit for Auto
Amp."
A/C system cannot be controlled. Go to Multifunction Switch System.AV-108, "
Multifunc-
tion Switch Cannot
Be Operated" (With-
out mobile enter-
tainment system) or
AV-249, "
Multifunc-
tion Switch Cannot
Be Operated" ( Wi t h
mobile entertain-
ment system)
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. (LAN)ATC-76, "
Mode
Door Motor Circuit"Mode door motor does not operate normally.
Upper ventilator outlet does not change.
Go to Trouble Diagnosis Procedure for Upper Ventilator Door
Motor. (LAN)ATC-79, "
Upper
Ventilator Door
Motor Circuit"Upper ventilator door motor does not oper-
ate normally.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor.
(LAN)AT C - 8 2 , "
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)AT C - 8 5 , "
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-88, "
Blower
Motor Circuit"
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch.AT C - 9 3 , "Magnet
Clutch Circuit"
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling.ATC-98, "
Insufficient
Cooling"
Go to Diagnosis Procedure for Insufficient Cooling.ATC-106, "
DIAG-
NOSIS PROCE-
DURE FOR
INSUFFICIENT
COOLING"
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.ATC-108, "Insuffi-
cient Heating"
Noise Go to Trouble Diagnosis Procedure for Noise.ATC-109, "Noise"
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis.ATC-110, "Self-diag-
nosis"
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.AT C - 111 , "Memory
Function"
Rear control switch does not operate. Go to Trouble Diagnosis Procedure for Rear Control Switch.AT C - 7 0 , "Rear Con-
trol Switch Circuit"

ATC-66
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
CHECKING DISCHARGE AIR (UPPER VENT SWITCH)
1. Press temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Press fan (UP:+) switch until Max. speed.
3. Set MODE switch (driver side) to VENT position.
4. Press UPPER VENT switch. AUTO indicator should illuminate.
5. Press temperature control (DOWN) switch (driver side) until 18°C (60°F) is displayed.
6. Confirm that discharger air come out.
7. Press UPPER VENT switch again. AUTO indicator should OFF.
If NG, go to trouble diagnosis procedure for AT C - 7 9 , "
Upper Ventilator Door Motor Circuit" .
If OK, continue the check.
CHECKING INTAKE AIR
1. Press intake switch. Recirculation indicator should illuminate.
2. Press intake switch again. Fresh indicator should illuminate.
3. Listen for intake door position change. (Slight change of blower sound can be heard.)
If NG, go to trouble diagnosis procedure for AT C - 8 5 , "
Intake Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at
FRESH when the D/F or DEF is selected.
CHECKING TEMPERATURE DECREASE
1. Press temperature control (DOWN) switch (driver side) until 18°C (60°F) is displayed.
2. Check for cold air at discharge air outlets.
If NG, go to trouble diagnosis procedure for AT C - 9 8 , "
Insufficient Cooling" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Press temperature control (UP) switch (driver side) until 32°C (90°F) is displayed.
2. Check for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for ATC-108, "
Insufficient Heating" .
If OK, continue the check.
CHECKING A/C SWITCH
1. Press AUTO switch and A/C switch.
2. A/C switch indicator will turn ON.

Confirm that the compressor clutch engages (sound or visual inspection).
If NG, go to trouble diagnosis procedure for AT C - 9 3 , "
Magnet Clutch Circuit" .
If OK, continue the check.
CHECKING AUTO MODE
1. Press AUTO switch and A/C switch.
2. Display should indicate AUTO.

Confirm that discharge air and blower speed will depend on ambient, in-vehicle, and set temperatures.
If NG, go to trouble diagnosis procedure for AT C - 6 7 , "
Power Supply and Ground Circuit for Auto Amp." , then
if necessary, trouble diagnosis procedure for AT C - 9 3 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to Incident Simulation Tests in GI-28,
"How to Perform Efficient Diagnosis for an Electrical Incident" and perform tests as outlined to simulate driv-
ing conditions environment. If symptom appears, refer to AT C - 4 1 , "
SYMPTOM TABLE" and perform applica-
ble trouble diagnosis procedures.

ATC-78
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
Mode Door Control Specification
COMPONENT DESCRIPTION
Mode Door Motor
The mode door motors are attached to the heater & cooling unit
assembly. It rotates so that air is discharged from the outlet set by
the unified meter and A/C amp. Motor rotation is conveyed to a link
which activates the mode door.
DIAGNOSIS PROCEDURE FOR MODE DOOR MOTOR
SYMPTOM: Mode door motor does not operate normally.
Perform diagnosis procedure. Refer to AT C - 7 1 , "
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT" .
RJIA1778E
RJIA4057E
RJIA4058E

TROUBLE DIAGNOSIS
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Revision: 2007 April2007 M35/M45
Upper Ventilator Door Control Specification
COMPONENT DESCRIPTION
Upper Ventilator Door Motor
The upper ventilator door motor is attached to the heater & cooling
unit assembly. It rotates so that air is discharged from the outlet set
by the unified meter and A/C amp. Motor rotation is conveyed to a
rod which activates the upper ventilator door.
DIAGNOSIS PROCEDURE FOR UPPER VENTILATOR DOOR MOTOR
SYMPTOM: Upper ventilator door motor does not operate normally.
Perform diagnosis procedure. Refer to AT C - 7 1 , "
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT" .
RJIA4061E
RJIA4062E