2006 INFINITI QX56 change time

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FOREWORD
This manual contains maintenance and repair procedures for the
2006 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-34
A/T CONTROL SYSTEM
Revision: November 20092006 QX56
Shift Change System Diagram
*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 ControlECS00CE1
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.
PCIA0013E
Select leverD position4 position 3 position 2 position
G ea r p osit io n 54432
Lock-up ×–×××
Slip lock-up ××–––
PCIA0014E

AT-84
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
CONSULT-II Function (A/T)ECS00CEP
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).
TCM diagnostic mode Description
WORK SUPPORT Supports 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 2 3.3 - 2.5 - 0.7 V
TCC SOLENOID When perform slip lock-up
0.2 - 0.4 A
When perform lock-up 0.4 - 0.6 A
SLCT LVR POSI Selector 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 driving Approximately matches the
speedometer reading.
ENGINE SPEED Engine running Closely matches the tachometer
reading.
LINE PRES SOL During driving 0.2 - 0.6 A
TURBINE REV During driving (lock-up ON) Approximately matches the
engine speed.
VHCL/S SE ·MTR During driving Approximately matches the
speedometer reading.

ATC-58
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Operational Check (Front)EJS003XL
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-131, "
Memory Function" .
If OK, continue with next check.
CHECKING BLOWER
1. Turn front blower control clockwise, blower should operate on low speed. The blower symbol should have one blade lit (on display).
2. Turn the front blower control dial again, and continue 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 AT C - 9 5 , "
DIAGNOSTIC PROCEDURE FOR BLOWER
MOTOR"AT C - 9 5 , "DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR" .
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 AT C - 3 0 , "
Discharge
Air Flow" .
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for AT C - 6 4 , "
Mode Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual 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 AT C - 8 3 , "
Intake Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual 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
1. Rotate temperature control dial (driver side or passenger side) counterclockwise until 16 °C (60 °F) is dis-
played.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-121,
"Insufficient Cooling" . If air mix door motor appears to be malfunctioning, go to AT C - 7 2 , "DIAGNOSTIC PRO-
CEDURE FOR AIR MIX DOOR MOTOR (DRIVER)" or AT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER)" .
If OK, continue the check. Conditions : Engine running and at normal operating temperature

TROUBLE DIAGNOSISATC-125
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AT C
Revision: November 2009 2006 QX56
TROUBLE DIAGNOSES FOR UNUSUAL PRESSURE
Whenever system′s high and/or low side pressure is unusual, diagnose using a manifold gauge. The marker
above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the stan-
dard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air temperature-
to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
Gauge indication Refrigerant cycleProbable causeCorrective action
Both high- and low-pressure sides
are too high. Pressure is reduced soon
after water is splashed on
condenser.
Excessive refrigerant charge
in refrigeration cycle
Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is
insufficient. 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
value quickly drops by
approximately 196 kPa (2
kg/cm
2 , 28 psi). It then
decreases gradually there-
after. Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure
decreases too slowly.)
↓
Air in refrigeration cycle
Evacuate and recharge sys-
tem.
Engine tends to overheat. Engine cooling systems mal-
function. Check and repair engine cool-
ing system.

An area of the low-pres-
sure 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
little compared with the
specification.
↓
Improper expansion valve
adjustment Replace expansion valve.
AC359A
Gauge indication
Refrigerant cycleProbable causeCorrective 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 tube or parts
located between compressor
and condenser are clogged or
crushed.

Check and repair or replace
malfunctioning parts.

Check oil for contamination.
AC360A

ATC-140
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
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 CircuitEJS003Y4
COMPONENT DESCRIPTION
The optical sensor is located in the 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 which 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 trees 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 the ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize the change in sunload, and the system will react accord-
ingly.
Temperature °C (°F) Resistance kΩ
− 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-8
AUDIO
Revision: November 20092006 QX56
System DescriptionEKS00BI8
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

through body grounds B117 and B132.
Audio signals are supplied

AUDIOAV-33
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AV
Revision: November 2009 2006 QX56
NOTE:
1. The following noise results from variations in field strength, such as fading noise and multi-path noise, or
external noise from trains and other sources. It is not a malfunction.

Fading noise: This noise occurs because of variations in the field strength in a narrow range due to moun-
tains or buildings blocking the signal.

Multi-path noise: This noise results from the waves sent directly from the broadcast station arriving at the
antenna at a different time from the waves which reflect off mountains or buildings.
FOR CD ONLY
FOR SATELLITE RADIO TUNER (FACTORY INSTALLED) ONLY
NOTE:
Pressing the SAT button, the display unit will display `NO SAT' when the following conditions exist:

Loss of power to the satellite radio tuner (factory installed)

Open or short in the REQ1, TXD, or RXD circuits.
If the satellite antenna is disconnected or inoperative, the display unit will display ANTENNA.
Noise InspectionEKS00BIH
The vehicle itself can be a source of noise if noise prevention parts or electrical equipment is malfunctioning.
Check if noise is caused and/or changed by engine speed, ignition switch turned to each position, and opera-
tion of each piece of electrical equipment, and determine the cause.
NOTE:
The source of the noise can be found easily by listening to the noise while removing the fuses of electrical
components, one by one.
TYPE OF NOISE AND POSSIBLE CAUSE
Symptom Possible cause
CD cannot be inserted.

CD

Audio unit
CD cannot be ejected.
The CD cannot be played.
The sound skips, stops suddenly, or is distorted.
Symptom
Possible cause
Inoperative

Satellite radio tuner (factory installed) power and ground circuit inspection.
Refer to AV- 3 7 , "
Satellite Radio Tuner (Factory Installed) Power and Ground
Supply Circuit Inspection" .

Satellite radio tuner (factory installed) communication circuit inspection.
Refer to AV- 3 8 , "
Satellite Radio Tuner (Factory Installed) Communication
Circuit Inspection" .
If above check is OK, replace satellite radio tuner (factory installed). Refer
to AV- 5 8 , "
SATELLITE RADIO TUNER" .
Right or left channel does not sound

Satellite radio tuner (factory installed) right channel audio signal circuit
inspection. Refer to AV-41, "
Satellite Radio Tuner (Factory Installed) Right
Channel Audio Signal Circuit Inspection" .

Satellite radio tuner (factory installed) left channel audio signal circuit
inspection. Refer toAV- 4 0 , "
Satellite Radio Tuner (Factory Installed) Left
Channel Audio Signal Circuit Inspection" .
If above check is OK, replace satellite radio tuner (factory installed). Refer to
AV- 5 8 , "
SATELLITE RADIO TUNER" .
Poor reception

Location of vehicle. Make certain vehicle is in an open area.

Satellite radio antenna or antenna feeder. Refer to AV- 6 2 , "Location of
Antenna" .
Noisy

Satellite radio tuner (factory installed) ground.

Satellite radio tuner (factory installed) harness shield wires.

Electrical equipment (generator, bonding wire, etc.). Refer to AV-33, "Noise
Inspection" .