2007 INFINITI QX56 change time

-2
This manual contains maintenance and repair procedures for the
2007 INFINITI QX56.
In order to assure your safety and the efficient functioning of the vehicle,
this manual should be read thoroughly. It is especially important that the
PRECAUTIONS in the GI section be completely understood before starting
any repair task.
All information in this manual is based on the latest product information
at the time of publication. The right is reserved to make changes in specifi-
cations and methods at any time without notice.
IMPORTANT SAFETY NOTICE
The proper performance of service is essential for both the safety of
the technician and the efficient functioning of the vehicle.
The service methods in this Service Manual are described in such a
manner that the service may be performed safely and accurately.
Service varies with the procedures used, the skills of the technician
and the tools and parts available. Accordingly, anyone using service
procedures, tools or parts which are not specifically recommended
by NISSAN must first be completely satisfied that neither personal
safety nor the vehicle’s safety will be jeopardized by the service
method selected.

AT-36
< SERVICE INFORMATION >
A/T CONTROL SYSTEM
*1: Full phase real-time feedback control monitors movement of gear ratio at gear change, and controls oil
pressure at real-time to achieve the best gear ratio.
Lock-up ControlINFOID:0000000003532235
The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to
increase power transmission efficiency.
The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid valve,
which is controlled by a signal from TCM, and the torque converter clutch control valve engages or releases
the torque converter clutch piston.
Lock-up Operation Condition Table
TORQUE CONVERTER CLUTCH CONTROL VALVE CONTROL
Lock-up Control System Diagram
Lock-up Released
• In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the
torque converter clutch solenoid and the lock-up apply pressure is drained.
In this way, the torque converter clutch piston is not coupled.
Lock-up Applied
• In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the
torque converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.
SMOOTH LOCK-UP CONTROL
PCIA0013E
Select lever D position 4 position 3 position 2 position
Gear position 5 4 4 3 2
Lock-up×–×××
Slip lock-up××–––
PCIA0014E

TROUBLE DIAGNOSIS
AT-83
< SERVICE INFORMATION >
D
E
F
G
H
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K
L
MA
B
AT
N
O
PCONSULT-II Function (A/T)INFOID:0000000003532259
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II REFERENCE VALUE
NOTICE:
1. The CONSULT-II electrically displays shift timing and lock-up timing (that is, operation timing of each sole-
noid).
Check for time difference between actual shift timing and the CONSULT-II display. If the difference is
noticeable, mechanical parts (except solenoids, sensors, etc.) may be malfunctioning. Check mechanical
parts using applicable diagnostic procedures.
2. Shift schedule (which implies gear position) displayed on CONSULT-II and that indicated in Service Man-
ual may differ slightly. This occurs because of the following reasons:
- Actual shift schedule has more or less tolerance or allowance,
- Shift schedule indicated in Service Manual refers to the point where shifts start, and
- Gear position displayed on CONSULT-II indicates the point where shifts are completed.
3. Display of solenoid valves on CONSULT-II changes at the start of shifting, while gear position is displayed
upon completion of shifting (which is computed by TCM).
9 B/R Starter relaySelector lever in “N”,“ P” positions. Battery voltage
Selector lever in other positions. 0V
10 B Ground Always 0V Te r m i n a l
No.Wire
colorItem Condition Data (Pyrex.)
TCM diagnostic mode Description
WORK SUPPORTSupports inspections and adjustments. Commands are transmitted to the TCM for setting the status
suitable for required operation, input/output signals are received from the TCM and received data is
displayed.
SELF-DIAG RESULTS Displays TCM self-diagnosis results.
DATA MONITOR Displays TCM input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.
FUNCTION TEST Conducted by CONSULT-II instead of a technician to determine whether each system is “OK” or “NG”.
ECU PART NUMBER TCM part number can be read.
Item name Condition Display value (Approx.)
ATF TEMP SE 1
0°C (32° F) - 20°C (68°F) - 80°C (176°F)3.3 - 2.7 - 0.9 V
ATF TEMP SE 23.3 - 2.5 - 0.7 V
TCC SOLENOIDWhen perform slip lock-up 0.2 - 0.4 A
When perform lock-up 0.4 - 0.6 A
SLCT LVR POSISelector lever in “N”,“P” position. N/P
Selector lever in “R” position. R
Selector lever in “D” position. D
Selector lever in “4” position. 4
Selector lever in “3” position. 3
Selector lever in “2” position. 2
Selector lever in “1” position. 1
VHCL/S SE·A/T During drivingApproximately matches the
speedometer reading.
ENGINE SPEED Engine runningClosely matches the tachometer
reading.

ATC-50
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Operational Check (Front)
INFOID:0000000003533249
The purpose of the operational check is to confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 90 °F or 32 °C.
2. Turn front blower control dial counterclockwise until system shuts OFF.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Turn front blower control counterclockwise until system shuts OFF.
If NG, go to trouble diagnosis procedure for ATC-112, "
Memory Function".
If OK, continue with next check.
CHECKING BLOWER
1. Turn front blower control clockwise, blower s hould operate on low speed. The blower symbol should have
one blade lit (on display).
2. Turn the front blower control dial again, and c ontinue checking blower speed and blower symbol until all
speeds are checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-78, "
Front Blower Motor Circuit".
If OK, continue with next check.
CHECKING DISCHARGE AIR
1. Press MODE switch four times and the DEF ( ) switch.
2. Each position indicator should change shape (on display).
3. Confirm that discharge air comes out according to the air distribution table. Refer to ATC-26, "
Discharge
Air Flow".
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for ATC-54, "
Mode Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or vis ual inspection) and intake door position is at fresh
when the DEF or D/F is selected.
CHECKING RECIRCULATION ( , ONLY)
1. Press recirculation ( ) switch one time. Recirculation indicator should illuminate.
2. Press recirculation ( ) switch one more time. Recirculation indicator should go off.
3. Listen for intake door position change (blower sound should change slightly).
If NG, go to trouble diagnosis procedure for ATC-70, "
Intake Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or vis ual inspection) and intake door position is at fresh
when the DEF or D/F is selected. REC ( ) is not allowed in DEF ( ) D/F ( ) or FOOT ( ).
CHECKING TEMPERATURE DECREASE
90 Stuck button ATC-123, "Removal and Installation"
92 Mode door motor circuit failureAT C - 5 4 , "Mode Door Motor Circuit"
Code No. Reference page
Conditions : Engine running and at normal operating temperature

ATC-54
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. Turn ignition switch OFF.
2. Check continuity between front air control harness connectorM49 terminal 1 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-123, "Removal
and Installation" .
NG >> Repair harness or connector.
Mode Door Motor CircuitINFOID:0000000003533252
SYMPTOM:
• Air outlet does not change.
• Mode door motor does not operate normally.
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OP ERATIONAL CHECK - DISCHARGE AIR
1. Press mode switch four times and then press the (DEF) switch. Each position indicator should change shape (on display).
2. Confirm that discharge air comes out according to the air distribution table. Refer to ATC-26, "
Discharge
Air Flow".
NOTE:
Confirm that the compressor clutch is engaged (visual inspection) and intake door position is at FRESH
when DEF ( ) or D/F ( ) is selected.
Can a symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.PERFORM COMPLETE OPERATIONAL CHECK
Perform a complete operational check and check for any symptoms. Refer to ATC-50, "
Operational Check
(Front)".
Can a symptom be duplicated?
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 4.
4.CHECK MODE DOOR OPERATION
Check and verify mode door mechanism for smooth operation in each mode.
OK or NG
OK >> GO TO 5.
NG >> Repair as necessary.
5.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis to check for any codes. Refer to ATC-48, "
A/C System Self-Diagnosis Function".
Are any self-diagnosis codes present?
YES >> Refer to ATC-48, "A/C System Self-Diagnosis Function".
NO >> GO TO 6.
6.CHECK THE MODE DOOR MOTOR PBR CIRCUIT 1 - Ground : Continuity should exist.
WJIA1351E

ATC-106
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
High-pressure Side is Too High and Low-pressure Side is Too Low
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
Both high- and low-pressure sides
are too high. Pressure is reduced soon af-
ter water is splashed on con-
denser.
Excessive refrigerant charge in
refrigeration cycle
Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is in-
sufficient. Insufficient condenser cooling
performance
↓
1. Condenser fins are
clogged.
2. Improper fan rotation of cooling fan • Clean condenser.
• Check and repair cooling fan
if necessary.
• Low-pressure pipe is not cold.
• When compressor is stopped high-pressure val-
ue quickly drops by approx-
imately 196 kPa (2 kg/cm
2 ,
28 psi). It then decreases
gradually thereafter. Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure decreas-
es too slowly.)
↓
Air in refrigeration cycle
Evacuate and recharge system.
Engine tends to overheat. Engine cooling systems mal-
function. Check and repair engine cool-
ing system.
• An area of the low-pressure pipe is colder than areas
near the evaporator outlet.
• Plates are sometimes cov- ered with frost. • Excessive liquid refrigerant
on low-pressure side
• Excessive refrigerant dis- charge flow
• Expansion valve is open a lit- tle compared with the speci-
fication.
↓
Improper expansion valve ad-
justment Replace expansion valve.
AC359A
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too high and
low-pressure side is too low.
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot.High-pressure tu
be or parts lo-
cated between compressor
and condenser are clogged or
crushed. • Check and repair or replace
malfunctioning parts.
• Check oil for contamination.
AC360A
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 be-
tween high- and low-pressure
sides. Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.
Replace compressor.
AC356A

TROUBLE DIAGNOSISATC-119
< SERVICE INFORMATION >
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AT C
N
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COMPONENT INSPECTION
In-vehicle Sensor
After disconnecting in-vehicle sensor connector M32, measure resis-
tance between terminals 1 and 4 at sensor component side, using
the table below.
If NG, replace in-vehicle sensor.
Optical Sensor CircuitINFOID:0000000003533268
COMPONENT DESCRIPTION
The optical sensor is located in t he center of the defroster grille. It
detects sunload entering through windshield by means of a photo
diode. The sensor converts the sunload into a current value which is
then input into the front air control.
OPTICAL INPUT PROCESS
The front air control includes a processing circuit whic h averages the variations in detected sunload over a
period of time. This prevents adjustments in the ATC system operation due to small or quick variations in
detected sunload.
For example, consider driving along a road bordered by an occasional group of large trees. The sunload
detected by the optical sensor will vary whenever the tr ees obstruct the sunlight. The processing circuit aver-
ages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily
obstructing the sunlight does not cause any change in t he ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize t he change in sunload, and the system will react accord-
ingly.
DIAGNOSTIC PROCEDURE FOR OPTICAL SENSOR
Temperature °C ( °F) Resistance k Ω
− 15 (5) 21.40
− 10 (14) 16.15
− 5 (23) 12.29
0 (32) 9.41
5 (41) 7.27
10 (50) 5.66
15 (59) 4.45
20 (68) 3.51
25 (77) 2.79
30 (86) 2.24
35 (95) 1.80
40 (104) 1.45 45 (113) 1.18
WJIA0825E
WJIA0569E

AV-6
< SERVICE INFORMATION >
AUDIO
System Description
INFOID:0000000003533664
Refer to Owner's Manual for audio system operating instructions.
Power is supplied at all times
• through 15A fuse [No. 17, located in the fuse block (J/B)]
• to subwoofer terminal 6
• through 20A fuse [No. 31, located in the fuse and fusible link box]
• to audio unit terminal 6
• to BOSE speaker amp. terminal 1
• to AV switch terminal 1 and
• to display control unit terminal 1.
With the ignition switch in the ACC or ON position, power is supplied
• through 10A fuse [No. 4, located in the fuse block (J/B)]
• to audio unit terminal 10 and
• to AV switch terminal 2 and
• to display control unit terminal 10.
With the ignition switch in the ON or START position, power is supplied
• through 10A fuse [No. 12, located in the fuse block (J/B)]
• to display control unit terminal 12.
Ground is supplied through the case of the audio unit.
Ground is also supplied
• to subwoofer terminal 5
• through body grounds B7 and B19 and
• to BOSE speaker amp. terminal 17
• to AV switch terminal 5 and
• to display unit terminal 1 and
• to display control unit terminal 3
• through body grounds M57, M61 and M79.
Then audio signals are supplied
• through audio unit terminals 1, 2, 3, 4, 13, 14, 15 and 16
• to BOSE speaker amp. terminals 23, 24, 25, 26, 27, 28, 29 and 30.
Audio signals are amplified by the BOSE speaker amp.
The amplified audio signals are supplied
• through BOSE speaker amp. terminals 2, 3, 9,10,11,12, 13, 14, 15, 16, 18 and 19
• to terminals + and - of front door speaker LH and RH and
• to terminals + and - of front tweeter LH and RH and
• to terminals + and - of center speaker and
• to terminals + and - of rear door speaker LH and RH and
• to terminals + and - of rear door tweeter LH and RH and
• to terminals 1 and 2 of subwoofer.
When one of steering wheel audio control switches is pushed, the resistance in steering switch circuit changes
depending on which button is pushed.
Rear Audio Remote Control Unit
Power is supplied
• from audio unit terminal 32
• to rear audio remote control unit terminal 13.
Ground is supplied
• to rear audio remote control unit terminal 15
7. Display control unit
M94, M958. Front tweeter RH
M 1119. AV Switch
M98
10. Audio unit
M43, M44, M45, M4611. BOSE speaker amp
M112, M11312. Satellite radio tuner (pre-wiring or factory
installed, if equipped)
M41
13. Steering wheel audio control switches 14. Front door speaker LH, RH
D12, D11215. Rear door tweeter LH, RH
D208, D308
16. Rear door speaker LH, RH
D207, D30717. Driver seat 18. Subwoofer
B72
19. Rear audio remote control unit
R204