INFINITI QX56 2008 Factory Service Manual
Manufacturer: INFINITI, Model Year: 2008, Model line: QX56, Model: INFINITI QX56 2008Pages: 4083, PDF Size: 81.73 MB
Page 3841 of 4083

VTL-1
VENTILATION, HEATER & AIR CONDITIONER
C
DE
F
G H
J
K L
M
SECTION VTL
A
B
VTL
N
O P
CONTENTS
VENTILATION SYSTEM
PRECAUTION ....... ........................................2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Precaution for Working with HFC-134a (R-134a) ......3
Precaution for Procedure without Cowl Top Cover ......3
PREPARATION ............................................4
PREPARATION .............................................. .....4
Commercial Service Tool .................................... ......4
FUNCTION DIAGNOSIS ...............................5
IN-CABIN MICROFILTER .............................. .....5
Description .......................................................... ......5
ON-VEHICLE MAINTENANCE .....................6
IN-CABIN MICROFILTER .............................. .....6
Removal and Installation ...........................................6
ON-VEHICLE REPAIR .... ..............................7
CONTROL UNIT ..................................................7
Removal and Installation ...........................................7
IN-VEHICLE SENSOR ................................... .....9
Removal and Installation ...........................................9
OPTICAL SENSOR ........................................ ....10
Removal and Installation .........................................10
INTAKE SENSOR ..............................................11
Removal and Installation .........................................11
BLOWER MOTOR .......................................... ....12
Component .......................................................... ....12
Removal and Installation ..................................... ....12
IN-CABIN MICROFILTER .................................14
Removal and Installation .........................................14
HEATER & COOLING UNIT ASSEMBLY ........15
Component ..............................................................15
Removal and Installation .........................................16
HEATER CORE .................................................18
Component ..............................................................18
Removal and Installation .........................................19
DEFROSTER DOOR MOTOR ..........................21
Removal and Installation .........................................21
INTAKE DOOR MOTOR ...................................22
Removal and Installation .........................................22
MODE DOOR MOTOR ......................................23
Components ............................................................23
Removal and Installation .........................................24
AIR MIX DOOR MOTOR ...................................25
Component ..............................................................25
Removal and Installation .........................................26
VARIABLE BLOWER CONTROL .....................28
Components ............................................................28
Removal and Installation .........................................29
DUCTS AND GRILLES .....................................30
Component ..............................................................30
Removal and Installation .........................................33
REFRIGERANT LINES .....................................35
Removal and Installation for Front Evaporator ........35
Removal and Installation for Rear Evaporator .........36
Removal and Installation for Rear Expansion
Valve ........................................................................
37
Revision: March 2010 2008 QX56
Page 3842 of 4083

VTL-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004884177
The Supplemental Restraint System such as “A IR 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 w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, 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 performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004884178
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III 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 NATS, an electrically controlled steering lock mech-
anism 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 pow er 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.
Revision: March 2010 2008 QX56
Page 3843 of 4083

PRECAUTIONSVTL-3
< PRECAUTION >
C
DE
F
G H
J
K L
M A
B
VTL
N
O P
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 al l control units using CONSULT-III.
Precaution for Working with HFC-134a (R-134a)INFOID:0000000001516598
WARNING:
• CFC-12 (R-12) refrigerant and HFC-134a (R-134a) refr igerant are not compatible. If the refrigerants
are mixed compressor failure is likely to occur. Refer to HA-4, "
Contaminated Refrigerant". To deter-
mine the purity of HFC-134a (R-134a) in the vehicle and recovery tank, use recovery/recycling equip-
ment and refrigerant identifier.
• Use only specified oil for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) components. If
oil other than that specified is used, compressor fa ilure is likely to occur.
• The specified HFC-134a (R-134a) oil rapidly absorb s moisture from the atmosphere. The following
handling precautions must be observed:
- When removing refrigerant components from a vehicle, immediately cap (seal) the component to
minimize the entry of mois ture from the atmosphere.
- When installing refrigerant components to a vehicle, do not remove the caps (unseal) until just
before connecting the co mponents. Connect all refrigerant lo op components as quickly as possible
to minimize the entry of moisture into system.
- Only use the specified oil from a sealed container. Immediately r eseal containers of oil. Without
proper sealing, oil will become moisture saturat ed and should not be used.
- Avoid breathing A/C refrigerant and oil vapor or mist. Exposure may irritate eyes, nose and throat.
Remove HFC-134a (R-134a) from the A/C system usi ng certified service equipment meeting require-
ments of SAE J2210 [HFC-134a (R-134a) recycling eq uipment], or J2209 [HFC-134a (R-134a) recovery
equipment]. If accidental system discharge occurs , ventilate work area before resuming service.
Additional health and safety information may be ob tained from refrigerant and oil manufacturers.
- Do not allow A/C oil to come in contact with styrofoam parts. Damage may result.
Precaution for Procedur e without Cowl Top CoverINFOID:0000000001516599
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
PIIB3706J
Revision: March 2010 2008 QX56
Page 3844 of 4083

VTL-4
< PREPARATION >
PREPARATION
PREPARATION
PREPARATION
Commercial Service ToolINFOID:0000000001516600
Tool nameDescription
Power tool Loosening bolts and nuts
PBIC0190E
Revision: March 2010 2008 QX56
Page 3845 of 4083

IN-CABIN MICROFILTERVTL-5
< FUNCTION DIAGNOSIS >
C
DE
F
G H
J
K L
M A
B
VTL
N
O P
FUNCTION DIAGNOSIS
IN-CABIN MICROFILTER
DescriptionINFOID:0000000001516601
FUNCTION
The air inside the passenger compartment is filtered by the in-cabin
microfilters when the heater or A/C controls are set on either the
recirculation or fresh mode. The two in-cabin microfilters are located
in the front heater and cooling unit assembly. The rear heater and
cooling unit assembly only draws in air from the passenger compart-
ment to recirculate into the passenger compartment, so the rear
heater and cooling unit assembly is not equipped with in-cabin
microfilters.
REPLACEMENT TIMING
Replacement of the two in-cabin microfilters is recommended on a regular interval depending on the driving
conditions. Refer to MA-8, "
Introduction of Periodic Maintenance". It may also be necessary to replace the two
in-cabin microfilters as part of a component r eplacement if the in-cabin microfilters are damaged.
LJIA0012E
Revision: March 2010 2008 QX56
Page 3846 of 4083

VTL-6
< ON-VEHICLE MAINTENANCE >
IN-CABIN MICROFILTER
ON-VEHICLE MAINTENANCE
IN-CABIN MICROFILTER
Removal and InstallationINFOID:0000000001516602
REPLACEMENT PROCEDURE
1. Remove the glove box assembly from the instrument panel. Refer to IP-17, "Removal and Installation".
2. Remove the screw and remove the in-cabin microfilter cover as shown.
3. Remove the two in-cabin microf ilters from the front heater and
cooling unit assembly housing.
4. Insert the first new in-cabin micr ofilter into the front heater and
cooling unit assembly housing and slide it over to the right.
Insert the second new in-cabin mi crofilter into the front heater
and cooling unit assembly housing as shown.
NOTE:
The in-cabin microfilters are marked with air flow arrows. The
end of the microfilter with the arro w should face the rear of the
vehicle. The arrows should point downward.
5. Install the in-cabin microfilter cover.
6. Install the glove box assembly in the instrument panel. Refer to IP-17, "
Removal and Installation".
7. Fill out the date information on the small replac ement label and attach it to the glove box lid.
LJIA0134E
LJIA0148E
LJIA0134E
Revision: March 2010 2008 QX56
Page 3847 of 4083

CONTROL UNITVTL-7
< ON-VEHICLE REPAIR >
C
DE
F
G H
J
K L
M A
B
VTL
N
O P
ON-VEHICLE REPAIR
CONTROL UNIT
Removal and InstallationINFOID:0000000001516603
A/C and AV SWITCH ASSEMBLY
Removal and Installation
The front A/C switch is integrated into the A/C and AV swit ch assembly in cluster lid C in the instrument panel.
Refer to AV-164, "
Removal and Installation".
A/C AUTO AMP.
Removal
1. Remove the display unit. Refer to AV-166, "Removal and Installation".
2. Remove the four screws (A) and remove the A/C auto amp. (1) from the back of the display unit (2).
Installation
Installation is in the reverse order of removal.
REAR AIR CONTROL (FRONT)
Removal
1. Remove the front roof console finisher from the headlining. Refer to INT-17, "Removal and Installation".
2. Remove the three screws (A) and remove the rear air control (front) (1).
Installation
Installation is in the reverse order of removal.
REAR AIR CONTROL (REAR)
Removal
1. Remove the rear roof console finisher from the headlining. Refer to INT-17, "Removal and Installation".
ALIIA0063ZZ
ALIIA0058ZZ
Revision: March 2010 2008 QX56
Page 3848 of 4083

VTL-8
< ON-VEHICLE REPAIR >
CONTROL UNIT
2. Remove the three screws (A) and remove the rear air control(rear) (1).
Installation
Installation is in the reverse order of removal.
ALIIA0059ZZ
Revision: March 2010 2008 QX56
Page 3849 of 4083

IN-VEHICLE SENSORVTL-9
< ON-VEHICLE REPAIR >
C
DE
F
G H
J
K L
M A
B
VTL
N
O P
IN-VEHICLE SENSOR
Removal and InstallationINFOID:0000000001516604
REMOVAL
1. Remove the lower instrument panel LH. Refer to IP-11, "Exploded View".
2. Remove the two screws (A) and remove the in-vehicle sensor (1).
INSTALLATION
Installation is in the reverse order of removal.
ALIIA0060ZZ
Revision: March 2010 2008 QX56
Page 3850 of 4083

VTL-10
< ON-VEHICLE REPAIR >
OPTICAL SENSOR
OPTICAL SENSOR
Removal and InstallationINFOID:0000000001516605
REMOVAL
1. Remove the defroster grille from the instrument panel. Refer to VTL-33, "Removal and Installation".
2. Disconnect the optical sensor connector (2).
3. Twist the optical sensor (1) counter clockwise to remove it from the defroster grille.
INSTALLATION
Installation is in the reverse order of removal.
ALIIA0061ZZ
Revision: March 2010 2008 QX56