intake INFINITI FX35 2008 Owner's Guide

ATC-70
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
SYSTEM DESCRIPTION
Unified meter and A/C amp. controls compressor operation by ambient temperature, intake air temperature
and signal from ECM.
Low Temperature Protection Control
Unified meter and A/C amp. will turn the compressor ON or OFF as determined by a signal detected by ambi-
ent sensor and intake sensor.
When ambient temperature is higher than −2 °C (28 °F), the compres-
sor turns ON. The compressor turns OFF when ambient temperature
is lower than −5 °C (23 °F).
When intake air temperature is higher than 1 °C (34 °F), the compres-
sor turns ON. The compressor turns OFF when intake air tempera-
ture is lower than −5 °C (23 °F).
DIAGNOSIS PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
1.CHECK AMBIENT SENSOR AND INTAKE SENSOR CIRCUIT
Check ambient sensor and intake sensor. Refer to ATC-43, "
Self-Diagnosis Function", see No. 9 and 11.
*4 "DIAGNOSIS PROCEDURE FOR
MAGNET CLUTCH" *5
AT C - 7 5 , "Insufficient Cooling"*6AT C - 5 0 , "Operational Check"
*7AT C - 4 3 , "Self-Diagnosis Function",
see No. 4 to 6. *8
AT C - 3 2 , "How to Perform Trouble Di-
agnosis for Quick and Accurate Re-
pair"
RHA094GB
SJIA0267E
SJIA1608E
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

TROUBLE DIAGNOSISATC-71
< SERVICE INFORMATION >
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OK or NG
OK >> GO TO 2.
NG >>  Malfunctioning ambient sensor: Refer to ATC-86, "
Ambient Sensor Circuit".
 Malfunctioning intake sensor: Refer to ATC-94, "
Intake Sensor Circuit".
2.PERFORM IPDM E/R AUTO ACTIVE TEST
Perform “IPDM E/R auto active test”. Refer to PG-20, "
Auto Active Test".
Does the magnet clutch operate?
YES >>  WITH CONSULT-III: GO TO 5  WITHOUT CONSULT-III: GO TO 6.
NO >> Check 10A fuse (No. 79, located in IPDM E/R). Refer to PG-23, "
IPDM E/R Terminal Arrange-
ment", and GO TO 3.
3.CHECK CIRCUIT CONTINUITY BETWEEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and compressor connector.
3. Check continuity between IPDM E/R harness connector E8 ter- minal 33 and compressor harness connector F2 terminal 1.
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4.CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct cur-
rent to terminal.
OK or NG
OK >> 1. Replace IPDM E/R. 2. Go to self-diagnosis procedure ATC-43, "
Self-Diag-
nosis Function" and perform self-diagnosis STEP-4.
Confirm that magnet clutch operation normal.
NG >> 1. Replace magnet clutch.
2. Go to self-diagnosis procedure ATC-43, "
Self-Diag-
nosis Function" and perform self-diagnosis STEP-4.
Confirm that magnet clutch operation normal.
5.CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal in “Data monitor”. Refer to ATC-32, "
CONSULT-III Function".
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6.CHECK CIRCUIT CONTINUITY BETWEEN BC M AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and unified meter and A/C amp. connector.
33 – 1 : Continui ty should exist.
RJIA2004E
RJIA2005E
A/C SW ON : AIR COND SW ON
A/C SW OFF : AIR COND SW OFF
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ATC-78
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Test Reading
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to -operating Pressure Table
TROUBLE DIAGNOSIS FOR UNUSUAL PRESSURE
Whenever system’s high and/or low side pressure(s) is/are unusual, diagnose using a manifold gauge. The
marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the
standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air tempera-
ture-to-operating pressure table).
Both High- and Low-pressure Sides are Too High
Hood Open
TEMP. Max. COLD
Mode switch (Ventilation) set
Intake switch (Recirculation) set
Fan (blower) speed Max. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Inside air (Recirculating air) at blower assembly inlet Discharge air temperature at center ventilator
°C ( °F)
Relative humidity
% Air temperature
°C ( °F)
50 - 60 20 (68) 11.2 - 13.2 (52 - 56)
25 (77) 12.2 - 14.8 (54 - 59)
30 (86) 15.5 - 18.6 (60 - 65)
35 (95) 21.0 - 24.5 (70 - 76)
40 (104) 28.7 - 32.6 (84 - 91)
60 - 70 20 (68) 13.2 - 15.2 (56 - 59)
25 (77) 14.8 - 17.3 (59 - 63)
30 (86) 18.6 - 21.6 (65 - 71)
35 (95) 24.5 - 28.0 (76 - 82)
40 (104) 32.6 - 36.5 (91 - 98)
Ambient air High-pressure (Discharge side)
kPa (kg/cm
2, psi) Low-pressure (Suction side)
kPa (kg/cm2, psi)
Relative humidity
% Air temperature
°C ( °F)
50 - 70 20 (68)
961 - 1,167
(9.8 - 11.9, 139 - 169) 216 - 265
(2.2 - 2.7, 31 - 38)
25 (77) 1,108 - 1,353
(11.3 - 13.8, 161 - 196) 230 - 281
(2.3 - 2.9, 33 - 41)
30 (86) 1,275 - 1,549
(13.0 - 15.8, 185 - 225) 261 - 320
(2.7 - 3.3, 38 - 46)
35 (95) 1,549 - 1,893
(15.8 - 19.3, 225 - 274) 297 - 364
(3.0 - 3.7, 43 - 53)
40 (104) 1,814 - 2,216
(18.5 - 22.6, 263 - 321) 357 - 435
(3.6 - 4.4, 52 - 63)
Vehicle condition Indoors or in the shade (in a well-ventilated place)
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ATC-80
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Low-pressure Side Sometimes Becomes Negative
Low-pressure Side Becomes Negative
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too low.  There is a big temperature
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.
 Liquid tank inlet and expan-
sion valve are frosted. Liquid tank inside is slightly
clogged.
 Replace liquid tank.
 Check lubricant for contami-
nation.
 Temperature of expansion valve inlet is extremely low
as compared with areas
near liquid tank.
 Expansion valve inlet is frosted.
 Temperature difference oc- curs somewhere in high-
pressure side. High-pressure pipe located be-
tween liquid tank and expan-
sion valve is clogged.
 Check and repair malfunc-
tioning parts.
 Check lubricant for contami- nation.
Expansion valve and liquid
tank are warm or slightly cool
when touched. Low refrigerant charge.
↓
Leaking fittings or compo-
nents.
Check refrigerant for leaks.
Refer to
ATC-138, "
Checking
of Refrigerant Leaks".
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted. Expansion valve closes a little
compared with the specifica-
tion.
↓
1. Improper expansion
valve adjustment.
2. Malfunctioning expansion
valve.
3. Outlet and inlet may be clogged.  Remove foreign particles by
using compressed air.
 Replace expansion valve.
 Check lubricant for contami-
nation.
An area of the low-pressure
pipe is colder than areas near
the evaporator outlet. Low-pressure pipe is clogged
or crushed.  Check and repair malfunc-
tioning parts.
 Check lubricant for contami- nation.
Air flow volume is not enough
or is too low. Evaporator is frozen.  Check intake sensor circuit.
Refer to AT C - 9 4 , "
Intake
Sensor Circuit".
 Replace compressor.
 Repair evaporator fins.
 Replace evaporator.
Refer to AT C - 6 4 , "
Blower
Motor Circuit".
AC353A
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes be-
comes negative.  Air conditioning system does
not function and does not cy-
clically cool the compart-
ment air.
 The system constantly func- tions for a certain period of
time after compressor is
stopped and restarted. Refrigerant does not discharge
cyclically.
↓
Moisture is frozen at expan-
sion valve outlet and inlet.
↓
Water is mixed with refrigerant.
 Drain water from refrigerant
or replace refrigerant.
 Replace liquid tank.
AC354A
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ATC-94
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
 When checking sunload sensor, select a place where sunshine directly on it.
If NG, replace sunload sensor.
Intake Sensor CircuitINFOID:0000000001328199
COMPONENT DESCRIPTION
Intake Sensor
The intake sensor is located on t he heater & cooling unit assembly. It
converts temperature of air after it passes through the evaporator
into a resistance value which is then input to the unified meter and A/
C amp.
DIAGNOSIS PROCEDURE FOR INTAKE SENSOR
SYMPTOM: Intake sensor circuit is open or shorted. (24 or −24 is
indicated on unified meter and A/C amp. as a result of performing
self-diagnosis STEP-2.)
1.CHECK VOLTAGE BETWEEN IN TAKE SENSOR AND GROUND
1. Disconnect intake sensor connector.
2. Turn ignition switch ON.
SHA930E
RJIA0928E
RJIA1458E
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TROUBLE DIAGNOSISATC-95
< SERVICE INFORMATION >
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3. Check voltage between intake sensor harness connector M254 terminal 2 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
2.CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between intake sensor harness connector M254 terminal 1 and unified meter and A/C amp. harness con-
nector M57 terminal 49.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
3.CHECK INTAKE SENSOR
Refer to "Intake Sensor".
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
NG >> 1. Replace intake sensor. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
4.CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between intake sensor harness connector M254 terminal 2 and unified meter and A/C amp. harness con-
nector M57 terminal 41.
4. Check continuity between intake sensor harness connector M254 terminal 2 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp. 2. Go to self-diagnosis ATC-43, "
Self-Diagnosis Function" and perform self-diagnosis STEP-2.
Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.
COMPONENT INSPECTION
Intake Sensor
2 – Ground : Approx. 5 V
RJIA2031E
1 – 49 : Continuity should exist.
RJIA2032E
2 – 41 : Continuity should exist.
2 – Ground : Continuity should not exist.
RJIA2033E
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ATC-96
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
After disconnecting intake sensor connector M254, measure resis-
tance between terminals 1 and 2 at sensor side. Refer to the table
below.
If NG, replace intake sensor.
Temperature °C ( °F) Resistance k Ω
− 15 (5) 12.34
− 10 (14) 9.62
− 5 (23) 7.56
0 (32) 6.00
5 (41) 4.80
10 (50) 3.87
15 (59) 3.15
20 (68) 2.57
25 (77) 2.12
30 (86) 1.76
35 (95) 1.47
40 (104) 1.23 45 (113) 1.04
RJIA2034E
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ATC-102
< SERVICE INFORMATION >
INTAKE SENSOR
INTAKE SENSOR
Removal and InstallationINFOID:0000000001328205
REMOVAL
1. Remove low-pressure pipe 2 and high-pressure pipe 3. Refer to ATC-133, "Removal and Installation of
Low-Pressure Pipe 2 and High-pressure Pipe 3".
CAUTION:
Cap or wrap the joint of evaporator, low-pressure pipe 1 and high-pressure pipe 2 with suitable
material such as vinyl tape to avoid the entry of air.
2. Slide evaporator to passenger side, and then remove intake sensor.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:
 Replace O-rings of low-pressure pipe 1, 2 and high-p ressure pipe 2, 3 with new ones, and then apply
compressor oil to it when installing it.
 Mark the mounting position of intake sensor bracket prior to removal so that the reinstalled sensor
can be located in the same position.
 Female-side piping connection is thin and easy to deform. Slowly insert the male-side piping
straight in axial direction.
 Insert piping securely until a click is heard.
 After piping connection is comp leted, pull male-side piping by hand to make sure that connection
does not come loose.
 When recharging refrigerant, check for leaks.
RJIA0928E
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3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

BLOWER UNITATC-103
< SERVICE INFORMATION >
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BLOWER UNIT
Removal and InstallationINFOID:0000000001328206
REMOVAL
1. Remove instrument passenger lower panel. Refer to IP-10.
2. Remove mounting nut, and then remove ECM with bracket attached.
3. Disconnect intake door motor connector and blower fan motor connector.
4. Remove harness clip from blower unit.
5. Remove mounting bolt and screws from blower unit. CAUTION:
Move blower unit rightward, and remove locating pin (1
part) and joint. Then remove blower unit downward.
6. Remove blower unit.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:
Make sure locating pin (1 part) and joint are securely inserted.
RJIA2039E
RJIA0943E
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ATC-104
< SERVICE INFORMATION >
BLOWER UNIT
Disassembly and Assembly
INFOID:0000000001328207
1. Adapter 2. Intake upper case 3. Filter cover
4. In-cabin microfilter 5. Intake lower case 6. Blower motor assembly
7. Motor cover 8. Intake door lever 2 9. Intake door motor
10. Intake door link 11. Intake door lever 3 12. Intake door 2
13. Intake door lever 1 14. Intake door 1 15. Intake bell mouth
SJIA0420E
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