air intake INFINITI M35 2007 Factory Owner's Guide

ATC-102
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
PERFORMANCE CHART
Test Condition
Testing must be performed as follows:
Test Reading (VQ35DE)
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to-operating Pressure Table
Vehicle condition Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door windows Open
Hood Open
TEMP. Max. COLD
Mode switch
(Ventilation) set
Intake switch
(Recirculation) set
Fan (blower) speedMax. 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 - 6020 (68) 5.5 - 7.2 (42 - 45)
25 (77) 8.5 - 10.9 (47 - 52)
30 (86) 12.3 - 15.1 (54 - 59)
35 (95) 16.5 - 19.8 (62 - 68)
40 (104) 21.0 - 25.0 (70 - 77)
60 - 7020 (68) 7.2 - 9.0 (45 - 48)
25 (77) 10.9 - 13.4 (52 - 56)
30 (86) 15.1 - 18.0 (59 - 64)
35 (95) 19.8 - 23.0 (68 - 73)
40 (104) 25.0 - 29.0 (77 - 84)
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 - 7020 (68)733 - 895
(7.5 - 9.1, 106.3 - 129.8)180 - 220
(1.8 - 2.2, 26.1 - 31.9)
25 (77)838 - 1,025
(8.5 - 10.5, 121.5 - 148.6)210 - 257
(2.1 - 2.6, 30.5 - 37.3)
30 (86)985 - 1,204
(10.0 - 12.3, 142.8 - 174.6)239 - 293
(2.4 - 3.0, 34.7 - 42.5)
35 (95)1,115 - 1,363
(11.4 - 13.9, 161.7 - 197.6)270 - 330
(2.8 - 3.4, 39.2 - 47.9)
40 (104)1,294 - 1,581
(13.2 - 16.1, 187.6 - 229.2)331 - 405
(3.4 - 4.1, 48.0 - 58.7)

TROUBLE DIAGNOSIS
ATC-105
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AT C
Revision: 2007 April2007 M35/M45
High-pressure Side is Too Low and Low-pressure Side is Too High
Both High- and Low-pressure Sides are Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too low and
low-pressure side is too high.High- and low-pressure sides
become equal soon after com-
pressor operation stops.Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.Replace compressor.
No temperature difference
between high- and low-pres-
sure sides.Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.Replace compressor.
AC356A
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
occurs somewhere in high-
pressure side.High-pressure pipe located
between liquid tank and
expansion 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-169, "
Checking
for 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 ATC-121, "
Intake
Sensor Circuit" .

Replace compressor.

Repair evaporator fins.

Replace evaporator.

Refer to AT C - 8 8 , "Blower
Motor Circuit" .
AC353A

TROUBLE DIAGNOSIS
ATC-121
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Revision: 2007 April2007 M35/M45
Intake Sensor CircuitNJS000H3
COMPONENT DESCRIPTION
Intake Sensor
The intake sensor is located on the 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 INTAKE SENSOR AND GROUND
1. Disconnect intake sensor connector.
2. Turn ignition switch ON.
3. Check voltage between intake sensor harness connector M82
terminal 1 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 M82
terminal 2 and unified meter and A/C amp. harness connector
M65 terminal 59.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connector.
RJIA4103E
RJIA4104E
1 – Ground : Approx. 5 V
RJIA4215E
2 – 59 : Continuity should exist.
RJIA4106E

ATC-122
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
3. CHECK INTAKE SENSOR
Refer to ATC-122, "
Intake Sensor" .
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 7 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> 1. Replace intake sensor.
2. Go to self-diagnosis AT C - 5 7 , "
FUNCTION CONFIRMATION PROCEDURE" 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 M82
terminal 1 and unified meter and A/C amp. harness connector
M65 terminal 43.
4. Check continuity between intake sensor harness connector M82
terminal 1 and ground.
OK or NG
OK >> 1. Replace unified meter and A/C amp.
2. Go to self-diagnosis AT C - 5 7 , "
FUNCTION CONFIRMATION PROCEDURE" and perform self-
diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG >> Repair harness or connector.
COMPONENT INSPECTION
Intake Sensor
After disconnecting intake sensor connector M82, measure resis-
tance between terminals 1 and 2 at sensor side. Refer to the table
below.
If NG, replace intake sensor.1 – 43 : Continuity should exist.
1 – Ground : Continuity should not exist.
RJIA4105E
Temperature °C (°F) Resistance kΩ
−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
RJIA4107E

ATC-128
INTAKE SENSOR
Revision: 2007 April2007 M35/M45
INTAKE SENSORPFP:27723
Removal and InstallationNJS000H9
REMOVAL
1. Remove low-pressure pipe 1 and high-pressure pipe 2. Refer to ATC-161, "Removal and Installation of
Low-pressure Pipe 1 and High-pressure Pipe 2" .
CAUTION:
Cap or wrap the joint of evaporator, low-pressure flexible hose and high-pressure pipe 1 with suit-
able 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 flexible hose, low-pressure pipe 1 and high-pressure pipe 1, 2
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 sen-
sor 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 completed, pull male-side piping by hand to make sure that connection
does not come loose.

When recharging refrigerant, check for leaks.
RJIA4103E

ATC-134
HEATER & COOLING UNIT ASSEMBLY
Revision: 2007 April2007 M35/M45
HEATER & COOLING UNIT ASSEMBLYPFP:27110
Removal and InstallationNJS000HF
REMOVAL
1. Use a refrigerant collecting equipment (for HFC-134a) to discharge the refrigerant.
2. Drain coolant from cooling system. Refer to CO-11, "
Changing Engine Coolant" (VQ35DE) or CO-40,
"Changing Engine Coolant" (VK45DE).
3. Remove cowl top cover. Refer to EI-18, "
COWL TOP" .
4. Disconnect low-pressure flexible hose and high-pressure pipe 1
from evaporator.
a. Set a disconnector [high-pressure side (SST: 9253089908), low-
pressure side (SST: 9253089916)] on A/C piping.
b. Slide a disconnector toward vehicle front until it clicks.
c. Slide A/C piping toward vehicle front and disconnect it.
CAUTION:
Cap or wrap the joint of low-pressure flexible hose, low-
pressure pipe 1 and high-pressure pipe 1, 2 with suitable
material such as vinyl tape to avoid the entry of air.
5. Remove electric throttle control actuator. Refer to EM-21,
"INTAKE MANIFOLD COLLECTOR" (VQ35DE) or EM-179, "INTAKE MANIFOLD" (VK45DE).
6. Disconnect two heater hoses from heater core.
7. Remove instrument panel & pad. Refer to IP-10, "
INSTRUMENT PANEL ASSEMBLY" .
8. Remove blower unit. Refer to ATC-129, "
BLOWER UNIT" .
9. Remove clips of vehicle harness from steering member.
10. Remove mounting nuts and bolts, and then remove instrument stays.
RJIA4117E
RJIA4118E
RJIA4119E

HEATER & COOLING UNIT ASSEMBLY
ATC-137
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Revision: 2007 April2007 M35/M45
Disassembly and AssemblyNJS000HG
1. Aspirator 2. Aspirator hose 3. Front heater duct (left)
4. Foot duct (left) 5. Ventilator door (left) 6. Ventilator door (right)
7. Foot duct (right) 8. Main link sub (right) 9. Ventilator door lever (right)
10. Ventilator door link (right) 11. Main link (right) 12. Mode door motor (passenger side)
13. Max. cool door link (right) 14. Air mix door motor (passenger side) 15. Intake sensor
16. Intake sensor bracket 17. O-ring 18. Low-pressure pipe 1
19. High-pressure pipe 2 20. Expansion valve 21. Cooler pipe grommet
22. Insulator 23. Evaporator cover adapter 24. Air mix door (Slide door)
25. Clip 26. Heater & cooling unit case (left) 27. Heater pipe grommet
28. Heater core 29. Upper ventilator door motor 30. Air mix door motor (driver side)
31. Mode door motor (driver side) 32. Main link (left) 33. Main link sub (left)
34. Ventilator door lever (left) 35. Center case 36. Max. cool door lever (right)
SJIA1772E

REFRIGERANT LINES
ATC-167
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Revision: 2007 April2007 M35/M45
Removal and Installation of EvaporatorNJS000HW
REMOVAL
1. Remove low-pressure pipe 1 and high-pressure pipe 2. Refer to ATC-161, "Removal and Installation of
Low-pressure Pipe 1 and High-pressure Pipe 2" .
CAUTION:
Cap or wrap the joint of evaporator, low-pressure flexible hose and high-pressure pipe 1 with suit-
able material such as vinyl tape to avoid the entry of air.
2. Slide evaporator, and then remove it from heater & cooling unit
assembly.
3. Remove intake sensor from evaporator, and then remove evap-
orator.
INSTALLATION
Installation is basically the reverse order of removal.
CAUTION:

Replace O-rings of low-pressure flexible hose, low-pressure pipe 1 and high-pressure pipe 1, 2
with new ones, and then apply compressor oil to it when installing it.

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 completed, pull male-side piping by hand to make sure that connection
does not come loose.

O-rings are different from low-pressure flexible hose (high-pressure pipe 1) and low-pressure pipe
1 (high-pressure pipe 2).

Mark the mounting position of intake sensor bracket prior to removal so that the reinstalled sen-
sor can be located in the same position.

When recharging refrigerant, check for leaks.
RJIA4103E
Low-pressure flexible hose bracket mounting bolt
: 4.2 N·m (0.43 kg-m, 37 in-lb)

REFRIGERANT LINES
ATC-171
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Revision: 2007 April2007 M35/M45
CHECKING PROCEDURE
To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette
smoke in the vicinity of the vehicle. Perform the leak test in calm area (low air/wind movement) so that the
leaking refrigerant is not dispersed.
1. Stop the engine.
2. Connect a suitable A/C manifold gauge set (SST: J-39183) to the A/C service valves.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm
2 , 50 psi) above 16°C (61°F). If less
than specification, recover/evacuate and recharge the system with the specified amount of refrigerant.
NOTE:
At temperatures below 16°C (61°F), leaks may not be detected since the system may not reach 345 kPa
(3.52 kg/cm
2 , 50 psi).
4. Perform the leak test from the high-pressure side (compressor discharge a to evaporator inlet h) to the
low-pressure side [evaporator drain hose i to shaft seal m(VQ35DE) or n(VK45DE)]. Refer to ATC-152,
"Components" . Perform a leak check for the following areas carefully. Clean the component to be
checked and move the leak detected probe completely around the connection/component.
Compressor
Check the fitting of high- and low-pressure flexible hoses, relief valve and shaft seal.
Condenser
Check the fitting of high-pressure flexible hose and pipe.
Liquid tank
Check the fitting of refrigerant pressure sensor.
Service valves
Check all around the service valves. Ensure service valve caps are secured on the service valves (to pre-
vent leaks).
NOTE:
After removing A/C manifold gauge set from service valves, wipe any residue from valves to prevent any
false readings by leak detector.
Cooling unit (Evaporator)
With engine OFF, turn blower fan on “High” for at least 15 seconds to dissipate any refrigerant trace in the
cooling unit. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer’s recommended
procedure for actual wait time) before inserting the leak detector probe into the drain hose.
Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water
or dirt that may be in the drain hose.
5. If a leak detector detects a leak, verify at least once by blowing compressed air into area of suspected
leak, then repeat check as outlined above.
6. Do not stop when one leak is found. Continue to check for additional leaks at all system components.
If no leaks are found, perform steps 7 - 10.
7. Start the engine.
8. Set the A/C control as follows;
a. A/C switch: ON
b. MODE door position: VENT (Ventilation)
c. Intake door position: Recirculation
d. Temperature setting: Max. cold
e. Fan speed: High
9. Run engine at 1,500 rpm for at least 2 minutes.
10. Stop the engine and perform leak check again following steps 4
through 6 above.
Refrigerant leaks should be checked immediately after stopping
the engine. Begin with the leak detector at the compressor. The
pressure on the high-pressure side will gradually drop after
refrigerant circulation stops and pressure on the low-pressure
side will gradually rise, as shown in the graph. Some leaks are
more easily detected when pressure is high.
SHA839E

WATER OUTLET AND WATER PIPING
CO-31
[VQ35DE]
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Revision: 2007 April2007 M35/M45
WATER OUTLET AND WATER PIPINGPFP:11060
ComponentsNBS004R5
Removal and InstallationNBS004R6
REMOVAL
1. Remove engine room cover (RH and LH). Refer to EM-15, "ENGINE ROOM COVER" .
2. Remove engine cover with power tool. Refer to EM-21, "
INTAKE MANIFOLD COLLECTOR" .
3. Remove air duct (inlet) and air cleaner case assembly. Refer to EM-19, "
AIR CLEANER AND AIR DUCT"
.
4. Remove front engine undercover with power tool.
5. Drain engine coolant from radiator drain plug at the bottom of radiator, and from water drain plug at the
front of cylinder block. Refer to CO-11, "
Changing Engine Coolant" and CO-24, "WATER PUMP" .
CAUTION:

Perform this step when the engine is cold.

Do not spill engine coolant on drive belts.
6. Remove radiator hose (upper) and heater hose.
7. Remove the following parts, when remove water outlet.

A/T fluid charging pipe: Refer to AT- 2 7 4 , "TRANSMISSION ASSEMBLY" .

Intake manifold collectors (upper and lower): Refer to EM-21, "INTAKE MANIFOLD COLLECTOR" .

Rocker cover (right bank): Refer to EM-53, "ROCKER COVER" .
8. Remove engine coolant temperature sensor as necessary.
CAUTION:
Be careful not to damage engine coolant temperature sensor.
1. Harness bracket 2. Water hose 3. Water bypass hose
4. Engine coolant temperature sensor 5. Gasket 6. Water outlet
7. Heater hose 8. Water pipe 9. Radiator hose (upper)
10. Heater pipe 11. Washer 12. O-ring
SBIA0484E