2007 INFINITI QX56 belt

ATC-1
AIR CONDITIONER
C
DE
F
G H
I
K L
M
SECTION AT C
A
B
AT C
N
O P
CONTENTS
AUTOMATIC AIR CONDITIONER
SERVICE INFORMATION .. ..........................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution for Working with HFC-134a (R-134a) ......3
Contaminated Refrigerant .........................................3
General Refrigerant Precaution ................................4
Precaution for Leak Detection Dye ...........................4
A/C Identification Label .............................................4
Precaution for Refrigerant Connection ......................4
Precaution for Service of Compressor ................ ......9
Precaution for Service Equipment ....................... ......9
PREPARATION ..................................................12
Special Service Tool ........................................... ....12
HFC-134a (R-134a) Service Tool and Equipment ....12
Commercial Service Tool ........................................14
REFRIGERATION SYSTEM ..............................16
Refrigerant Cycle ................................................ ....16
Refrigerant System Protection ................................16
Component Part Location ................................... ....17
OIL ......................................................................20
Maintenance of Oil Quantity in Compressor ....... ....20
AIR CONDITIONER CONTROL .........................22
Description .......................................................... ....22
Operation ................................................................22
Description of Control System .................................23
Control Operation ....................................................24
Discharge Air Flow ..................................................26
System Description (Front) .....................................27
System Description (Rear) .................................. ....28
CAN Communication System Description ...............29
TROUBLE DIAGNOSIS .....................................30
CONSULT-II Function (HVAC) ............................ ....30
CONSULT-II Function (BCM) ..................................31
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ................................................... ....
32
Component Parts and Harness Connector Loca-
tion ...........................................................................
32
Schematic ................................................................36
Wiring Diagram - A/C,A - .........................................37
Front Air Control Terminal and Reference Value ....47
A/C System Self-Diagnosis Function .......................48
Operational Check (Front) ................................... ....50
Operational Check (Rear) ........................................51
Power Supply and Ground Circuit for Front Air
Control ................................................................. ....
52
Mode Door Motor Circuit .........................................54
Air Mix Door Motor Circuit ................................... ....59
Intake Door Motor Circuit .........................................70
Defroster Door Motor Circuit ....................................74
Front Blower Motor Circuit .......................................78
Rear Blower Motor Circuit ................................... ....85
Rear Air Control Circuit ............................................93
Magnet Clutch Circuit ..............................................96
Insufficient Cooling ................................................100
Insufficient Heating ................................................108
Noise .....................................................................109
Self-Diagnosis .......................................................111
Memory Function ...................................................112
Water Valve Circuit ................................................113
Ambient Sensor Circuit ..........................................114
In-vehicle Sensor Circuit ........................................116
Optical Sensor Circuit ............................................119
Intake Sensor Circuit .............................................120
CONTROL UNIT ..............................................123
Removal and Installation .......................................123
AMBIENT SENSOR ........................................124
Removal and Installation .......................................124
IN-VEHICLE SENSOR ....................................125
Removal and Installation .......................................125
OPTICAL SENSOR .........................................126

PRECAUTIONSATC-3
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
SERVICE INFORMATION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000003533217
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 severi ty 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 SRS and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoper ative, 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 unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SRS section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
Precaution for Workin g with HFC-134a (R-134a)INFOID:0000000003533218
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 AT C - 3 , "
Contaminated Refrigerant". To
determine the purity of HFC-134a (R-134a) in the vehicle and recovery tank, use recovery/recycling
equipment 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 specifi ed 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 reseal 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.
Contaminated RefrigerantINFOID:0000000003533219
If a refrigerant other than pure HFC-134a (R-134a) is identified in a vehicle, your options are:
• Explain to the customer that environmental regulations prohibit the release of contaminated refrigerant into
the atmosphere.
• Explain that recovery of the contaminated refri gerant could damage your service equipment and refrigerant
supply.
• Suggest the customer return the vehicle to the locati on of previous service where the contamination may
have occurred.
• If you choose to perform the repair, recover the refrigerant using only dedicated equipment and contain-
ers. Do not recover contaminated refriger ant into your existing service equipment. If your facility does

TROUBLE DIAGNOSISATC-101
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
YES >> Refer to ATC-32, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" .
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 3.
4.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis Refer to ATC-48, "
A/C System Self-Diagnosis Function" .
OK or NG
OK >> GO TO 5.
NG >> Refer to ATC-48, "
A/C System Self-Diagnosis Function" .
5.CHECK DRIVE BELTS
Check compressor belt tension. Refer to EM-13, "
Checking Drive Belts" .
OK or NG
OK >> GO TO 6.
NG >> Adjust or replace compressor belt. Refer to EM-13, "
Removal and Installation" .
6.CHECK AIR MIX DOOR OPERATION
Check and verify air mix door me chanism for smooth operation.
Does air mix door operate correctly?
YES >> GO TO 7.
NO >> Repair or replace air mix door control linkage.
7.CHECK COOLING FAN MOTOR OPERATION
Check and verify cooling fan moto r for smooth operation. Refer to EC-469, "
Description" .
Does cooling fan motor operate correctly?
YES >> GO TO 8.
NO >> Check cooling fan motor. Refer to EC-469
.
8.CHECK WATER VALVE OPERATION
Check and verify water valve for smooth operation. Refer to ATC-113, "
Water Valve Circuit".
Does water valve operate correctly?
YES >> GO TO 8.
NO >> Check water valve circuit. Refer to ATC-113, "
Water Valve Circuit" .
9.CHECK RECOVERY/RECYCLING EQUIPMENT BEFORE USAGE
Check recovery/recycling equipment befor e connecting to vehicle. Verify there is no pressure in the recovery/
recycling equipment by checking the gauges. If pressure exists, recover refrigerant from equipment lines.
>> GO TO 9.
10.CHECK REFRIGERANT PURITY
1. Connect recovery/recycling equipment to vehicle.
2. Confirm refrigerant purity in supply tank us ing recovery/recycling and refrigerant identifier.
OK or NG
OK >> GO TO 10.
NG >> Check contaminated refrigerant. Refer to AT C - 3 , "
Contaminated Refrigerant" .
11 .CHECK FOR EVAPORATOR FREEZE UP
Start engine and run A/C. Check for evaporator freeze up.
Does evaporator freeze up?
YES >> Perform performance test diagnoses. Refer to "PERFORMANCE TEST DIAGNOSES" .
NO >> GO TO 11.

ATC-104
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
PERFORMANCE CHART
Test Condition
Testing must be performed as follows:
*1ATC-155, "Removal and Installation
for Compressor Clutch"
*2AT C - 7 8 , "Front Blower Motor Circuit"*3EM-13, "Checking Drive Belts"
WJIA1371E

ATC-110
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
*1ATC-154, "Removal and Installation
for Compressor". *2
ATC-154, "
Removal and Installation
for Compressor". *3
AT C - 2 0 , "
Maintenance of Oil Quanti-
ty in Compressor".
*4 AT C - 5 0 , "
Operational Check (Front)"
or AT C - 5 1 , "
Operational Check
(Rear)" . *5
EM-13, "
Checking Drive Belts".
WJIA1972E

ATC-154
< SERVICE INFORMATION >
REFRIGERANT LINES
Removal and Installation for Compressor
INFOID:0000000003533293
A/C Compressor Mounting
REMOVAL
1. Discharge the refrigerant. Refer to ATC-150, "HFC-134a (R-134a) Service Procedure".
2. Remove the front right wheel and tire assembly. Refer to WT-7, "
Rotation".
3. Remove the engine under cover and the splash shield using power tool.
4. Remove the engine air cleaner and air ducts. Refer to EM-15
.
5. Remove the drive belt. Refer to EM-13
.
6. Disconnect the compressor electrical connector.
7. Disconnect the high-pressure flexible hose and low- pressure flexible hose from the compressor.
CAUTION:
Cap or wrap the joint of the pipe with suitable mate rial such as vinyl tape to avoid the entry of air.
8. Remove the compressor bolts and nut using power tools.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-rings of the low-pressure flexibl e hose and high-pressure flexible hose with new
ones, apply compressor oil to the O-rings when installing them.
• After recharging the A/C system with refrigerant, check for leaks.
WJIA0958E

REFRIGERANT LINESATC-157
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
3. Install the pulley assembly using Tool and a wrench, then install the snap ring using snap ring pliers.
4. Install the clutch disc on the co mpressor shaft, together with the
original shim(s). Press the clutch disc down by hand.
5. Install the clutch pulley bolt using Tool, to prevent the clutch disc from turning and tighten the bolt to specification.
CAUTION:
After tightening the clutch pul ley bolt, check that the clutch
pulley rotates smoothly.
6. Check the pulley clearance all the way around the clutch disc as shown.
7. If the specified clearance is not obtained, replace the adjusting spacer to readjust.
8. Connect the compressor electrical connector.
9. Install the drive belt. Refer to EM-13
.
10. Install the engine under cover and the splash shield. Tool number : — (J-38873-A)
WJIA1016E
WHA184
Tool number : J-44614
WHA229
Clutch disc-to-pulley clearance : 0.3 - 0.6 mm
(0.012 - 0.024 in)
WHA194

REFRIGERANT LINESATC-161
< SERVICE INFORMATION >
C
DE
F
G H
I
K L
M A
B
AT C
N
O P
5. Remove the front and rear bumper fascia. Refer to EI-12 (front), EI-14 (rear).
6. Reposition the front fender protector out of the way. Refer to EI-22
.
7. Disconnect the chassis harness connector.
8. Remove the spare wheel and tire.
9. Remove the tailpipe and tailpipe hanger bracket. Refer to EX-3, "
Removal and Installation".
10. Remove the seatbelt latch anchor. Refer to RSU-21, "
Component".
11. Remove the front floor heat shield.
12. Disconnect each end of the underfloor rear high- and low-pressure A/C and heater core pipes. Refer to
ATC-152, "
Component".
CAUTION:
Cap or wrap the joint of the pipes with suitable material such as viny l tape to avoid the entry of air.
13. Set two suitable jacks at the RH body mount points to support the vehicle body when it is separated from the RH side of the frame.
14. Remove the RH body mount bolts. Refer to BL-135, "
Body Mounting".
15. Use the vehicle hoist to lower the RH side of the frame from the RH side of the body [approximately 305
mm (12 in)] until there is sufficient clearance to remove the underfloor rear high- and low-pressure A/C
and heater core pipes from between the body and the frame.
16. Remove the underfloor rear high- and low-pressure A/ C and heater core pipes from the back of the vehi-
cle.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-152, "
Component".
CAUTION:
• Replace the O-ring of the high/low-pressure pipe with a new one, then apply compressor oil to it
when installing it.
• After charging refrigerant, check for leaks.
Removal and Installation for Refrigerant Pressure SensorINFOID:0000000003533301
REMOVAL
1. Discharge the refrigerant. Refer to ATC-150, "HFC-134a (R-134a) Service Procedure".
2. Disconnect the refrigerant pressu re sensor electrical connector
and remove the refrigerant pressure sensor from the condenser.
CAUTION:
Be careful not to damage the condenser fins.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-152, "
Component".
CAUTION:
• Be careful not to damage the condenser fins.
• Replace the O-ring of the refrig erant pressure sensor with a new one, then apply compressor oil to it
when installing it.
• After charging refrigerant, check for leaks.
Removal and Installation for CondenserINFOID:0000000003533302
REMOVAL
1. Discharge the refrigerant. Refer to .
LJIA0145E