2007 INFINITI QX56 ABS

FRONT SEAT
SE-87
< SERVICE INFORMATION >
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4. From inside of the seatback, squeeze the headrest holder tabs
at the base of the stay pipe and pull up to remove.
NOTE:
Before installing the headrest holder, check its orientation (front/
rear and right/left).
Removal of seatback assembly
1. After completing the steps 1 and 2 of "Seatback Trim and Pad", remove the side air bag harness connec-
tor from the seat cushion.
2. Remove the mounting bolts (2 for each side) and seatback assembly.
Installation of seatback assembly
• Installation is in the reverse order of removal.
SEAT CUSHION TRIM AND PAD (DRIVER) OR SEAT CUSHION ASSEMBLY (PASSENGER)
CAUTION:
• Front passenger seat is equipped with an Occupant Classification System sensor and control mod-
ule. Do not disassemble front passenger seat cushion assembly or remove the trim as this will affect
the Occupant Classification System calibration.
• Always replace passenger seat cushion as an assembly.
• When removed, the passenger seat cushion must always be placed pan side UP to prevent damage.
• During installation, the wire harness clips must be reinstalled in the holes they were originally in.
Do not add clips.
• The Occupant Classification System control module can only be replaced as part of the seat cushion
assembly.
NOTE:
If the vehicle has been involved in a collision the seat must be inspected for damage. Refer to SRS-49
.
1. Remove the power seat switch knobs, power seat switch
escutcheon and lumbar switch bezel.
2. Remove the power seat and power lumbar switches.
3. Remove four bolts and the seat cushion assembly.
4. Remove the retainer on the seat cushion frame, then remove the harness connector for the seat heater.
LRS023
LIIA1581E
SIIA0503E

SPIRAL CABLE
SRS-37
< SERVICE INFORMATION >
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SRS
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SPIRAL CABLE
Removal and InstallationINFOID:0000000003532874
REMOVAL
CAUTION:
• Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least
3 minutes.
• When servicing the SRS, do not work from directly in front of air bag module.
1. Remove the steering wheel. Refer to PS-7
.
2. Remove the column cover upper and lower.
3. Remove wiper and washer switch connector, then pinch the tabs
at wiper and washer switch base and slide away from steering
column to remove.
4. While pressing tabs, pull lighting and turn signal switch toward
driver door and disconnect from base.
WHIA0233E
1. Steering wheel 2. Lighting and turn signal switch 3. Wiper and washer switch
4. Spiral cable 5. Driver air bag module connector 6. Column cover upper
7. Column assembly 8. Column cover lower 9. Screw (Do not remove)
10. Screw
LHIA0034E
LHIA0035E

TF-1
DRIVELINE/AXLE
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SECTION TF
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CONTENTS
TRANSFER
SERVICE INFORMATION ............................3
PRECAUTIONS ...................................................3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
3
Precaution for Transfer Assembly and Transfer
Control Unit Replacement .........................................
3
Precaution .................................................................4
Service Notice ...........................................................4
PREPARATION ...................................................6
Special Service Tool .................................................6
Commercial Service Tool ..........................................9
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING ............................
10
NVH Troubleshooting Chart ....................................10
TRANSFER FLUID .............................................11
Replacement ...........................................................11
Inspection ................................................................11
ALL-MODE 4WD SYSTEM ................................12
Cross-Sectional View ..............................................12
Power Transfer ........................................................12
System Description .................................................14
Schematic ...............................................................19
CAN Communication ...............................................20
TROUBLE DIAGNOSIS .....................................21
How to Perform Trouble Diagnosis .........................21
Location of Electrical Parts ......................................22
Circuit Diagram .......................................................23
Wiring Diagram - T/F - .............................................24
Inspections Before Trouble Diagnosis ....................31
Trouble Diagnosis Chart by Symptom ....................34
Transfer Control Unit Input/Output Signal Refer-
ence Value ..............................................................
35
CONSULT-II Function (ALL MODE AWD/4WD) .....42
Self-Diagnosis Procedure .......................................48
TROUBLE DIAGNOSIS FOR SYSTEM ............51
Power Supply Circuit for Transfer Control Unit ........51
Transfer Control Unit ...............................................53
Output Shaft Revolution Signal (TCM) ....................53
Vehicle Speed Sensor (ABS) ..................................54
Neutral-4LO Switch .................................................54
4WD Shift Switch .....................................................57
Wait Detection Switch ..............................................60
PNP Switch Signal (TCM) .......................................63
Actuator Motor .........................................................64
Actuator Position Switch ..........................................69
Transfer Control Device ...........................................72
Engine Speed Signal (ECM) ....................................76
Clutch Pressure Solenoid ........................................76
2-4WD Solenoid ......................................................80
Transfer Motor .........................................................84
Transfer Fluid Temperature .....................................90
Clutch Pressure Switch ...........................................92
Line Pressure Switch ...............................................94
Throttle Position Signal (ECM) ................................97
ABS Operation Signal (ABS) ...................................97
VDC Operation Signal (ABS) ...................................98
TCS Operation Signal (ABS) ...................................98
CAN Communication Line .......................................99
ATP Switch ..............................................................99
TROUBLE DIAGNOSIS FOR SYMPTOMS ....102
4WD Shift Indicator Lamp and 4LO Indicator
Lamp Do Not Turn ON ...........................................
102
4WD Warning Lamp Does Not Turn ON ...............104
4WD Shift Indicator Lamp or 4LO Indicator Lamp
Does Not Change ..................................................
107
ATP Warning Lamp Turns ON ...............................109
4LO Indicator Lamp Repeats Flashing ..................110
4WD Warning Lamp Flashes Rapidly ....................111
4WD Warning Lamp Flashes Slowly .....................112
Heavy Tight-corner Braking Symptom Occurs ......113
4WD System Does Not Operate ............................114
TRANSFER CONTROL UNIT .........................115
Removal and Installation .......................................115

TF-20
< SERVICE INFORMATION >
ALL-MODE 4WD SYSTEM
CAN Communication
INFOID:0000000003532519
SYSTEM DESCRIPTION
Refer to LAN-4.
ABS actuator and electric unit
(control unit)Transmits vehicle speed signal via CAN communication to transfer control unit.
TCMTransmits the following signals via CAN communication to transfer control unit.
• Output shaft revolution signal
• A/T position indicator signal (PNP switch signal)
ECMTransmits the following signals via CAN communication to transfer control unit.
• Engine speed signal
• Accelerator pedal position signal Component parts Function

TF-36
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
ATP SWITCH [ON/OFF] Condition of ATP switch• Vehicle stopped
• Engine running
• A/T selector lever “N”
• Brake pedal depressed4WD shift switch
: 4H to 4LO or 4LO to 4H
(While actuator motor is
operating.) ON
Except the above OFF
WAIT DETCT SW [ON/
OFF]Condition of wait detec-
tion switch• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD,
AUTO or 4HOFF
4WD shift switch: 4H to
4LO (While actuator mo-
tor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON
LINE PRES SW [ON/
OFF]Condition of line pres-
sure switch• A/T selector lever “D” position
• 4WD shift switch: 2WD, AUTO or 4HON
• Except the above
• The vehicle has been left at
room temperature for 5
minutes and more with ig-
nition switch in “OFF” posi-
tion.• Ignition switch: ON
• A/T selector lever: “P”
or "N" position
• 4WD shift switch: other
than AUTOOFF
CL PRES SW [ON / OFF]Condition of clutch pres-
sure switch• Vehicle stopped
• Engine running
• A/T selector lever “D” position
• 4WD shift switch: AUTO or 4H (“Wait” function is not op-
erating.)ON
• Vehicle stopped
• Engine running
• 4WD shift switch: 2WD (“Wait” function is not operat-
ing.)OFF
N POSI SW AT [ON/
OFF]Input condition from A/T
PNP switch• Vehicle stopped
• Engine running
• Brake pedal depressedA/T selector lever posi-
tion: NON
Except the above OFF
R POSI SW AT [ON/
OFF]Input condition from A/T
PNP switch• Vehicle stopped
• Engine running
• Brake pedal depressedA/T selector lever posi-
tion: RON
Except the above OFF
P POSI SW AT [ON/OFF]Input condition from A/T
PNP switch• Vehicle stopped
• Engine running
• Brake pedal depressedA/T selector lever posi-
tion: PON
Except the above OFF
ABS OPER SW [ON/
OFF]Condition of ABS operat-
ingABS is operating. ON
ABS is not operating. OFF
VDC OPER SW [ON/
OFF]Condition of VDC operat-
ingVDC is operating. ON
VDC is not operating. OFF
TCS OPER SW [ON/
OFF]Condition of TCS operat-
ingTCS is operating. ON
TCS is not operating. OFF
THROTTLE POSI [0.0/8]Condition of throttle
openingWhen depressing accelerator pedal
(Value rises gradually in response to throttle position.)0.0/8 - 8.0/8
4WD MODE [AUTO/
LOCK/2WD/4L]Control status of 4WD
(Output condition of 4WD
shift indicator lamp and
4LO indicator lamp)• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD 2WD
4WD shift switch: AUTO AUTO
4WD shift switch: 4H LOCK
4WD shift switch: 4LO 4L Monitored item [Unit] Content Condition Display value

TROUBLE DIAGNOSIS
TF-43
< SERVICE INFORMATION >
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CONSULT-II START PROCEDURE
Refer to GI-36, "CONSULT-II Start Procedure" .
SELF-DIAG RESULT MODE
Operation Procedure
1. Perform “CONSULT-II Start Procedure”. Refer to GI-36, "CONSULT-II Start Procedure".
2. With engine at idle, touch “SELF-DIAG RESULTS”.
Display shows malfunction experienced since the last erasing
operation.
NOTE:
•The details for “TIME” are as follow:
-“0”: Error currently detected with transfer control unit.
-Except for “0”: Error detected in the past and memorized
with transfer control unit.
Detects frequency of driving after DTC occurs (frequency
of turning ignition switch “ON/OFF”).
Display Item List
SDIA2687E
Items (CONSULT-II screen
terms)Diagnostic item is detected when... Check item
CONTROL UNIT 1
[P1802]• Malfunction is detected in the memory (RAM) system of transfer
control unit.TF-53, "
Transfer Control Unit"
CONTROL UNIT 2
[P1803]• Malfunction is detected in the memory (ROM) system of transfer
control unit.TF-53, "Transfer Control Unit"
CONTROL UNIT 3
[P1804]• Malfunction is detected in the memory (EEPROM) system of trans-
fer control unit.TF-53, "Transfer Control Unit"
VHCL SPEED SEN·AT
[P1807]• Malfunction is detected in output shaft revolution signal that is out-
put from TCM through CAN communication.
• Improper signal is input while driving.TF-53, "Output Shaft Revolution
Signal (TCM)"
VHCL SPEED SEN·ABS
[P1808]• Malfunction is detected in vehicle speed signal that is output from
ABS actuator and electric unit (control unit) through CAN commu-
nication.
• Improper signal is input while driving.TF-54, "Vehicle Speed Sensor
(ABS)"
CONTROL UNIT 4
[P1809]• AD converter system of transfer control unit is malfunctioning.TF-53, "Transfer Control Unit"
4L POSI SW TF
[P1810]• Improper signal from neutral-4LO switch is input due to open or
short circuit.TF-54, "Neutral-4LO Switch"
BATTERY VOLTAGE
[P1811]• Power supply voltage for transfer control unit is abnormally low
while driving.TF-51, "Power Supply Circuit for
Transfer Control Unit"
4WD MODE SW
[P1813]• More than two switch inputs are simultaneously detected due to
short circuit of 4WD shift switch.TF-57, "4WD Shift Switch"
4WD DETECT SWITCH
[P1814]• Improper signal from wait detection switch is input due to open or
short circuit.TF-60, "Wait Detection Switch"
PNP SW/CIRC
[P1816]• When A/T PNP switch signal is malfunction or communication er-
ror between the vehicles.TF-63, "PNP Switch Signal
(TCM)"
SHIFT ACTUATOR
[P1817]• Motor does not operate properly due to open or short circuit in ac-
tuator motor.
• Malfunction is detected in the actuator motor. (When 4WD shift
switch is operated and actuator motor is not operated)
• Malfunction is detected in transfer shift high relay and transfer shift
low relay.TF-64, "Actuator Motor"
SHIFT ACT POSI SW
[P1818]• Improper signal from actuator position switch is input due to open
or short circuit.
• Malfunction is detected in the actuator position switch.TF-69, "Actuator Position Switch"

TF-44
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
CAUTION:
• If “CAN COMM CIRCUIT [U1000]” is displayed with other DTCs, first perform the trouble diagnosis for CAN communication
line.
• If “VHCL SPEED SEN·AT [P1808]”, “ABS OP SIG [P1830]”, “VDC OP SIG [P1831]” or “TCS OP SIG [P1832]” is displayed, first
perform the trouble diagnosis for ABS system.
• If “VHCL SPEED SEN·AT [P1808]”, is displayed, first perform the trouble diagnosis for A/T system.
NOTE:
• If "SHIFT ACT POSI SW [P1818]" or “SHIFT ACT CIR [P1819]” is displayed, first erase self-diagnostic results. ("SHIFT ACT POSI SW
[P1818]" or “SHIFT ACT CIR [P1819]” may be displayed after installing transfer control unit or transfer assembly.)
• If “CL PRES SW [P1827]” or “LINE PRES SW [P1828]” is displayed only while driving in reverse, check the continuity of “R” position
on A/T PNP switch. When there is nothing wrong with the electrical system, check the hydraulic system.
How to Erase Self-diagnostic Results
1. Perform applicable inspection of malfunctioning item and then repair or replace.
SHIFT ACT CIR
[P1819]• Transfer control device actuator circuit is shorted or open. (Mal-
functions are detected when transfer shift relay circuit is open/
shorted or relay monitor circuit is open/shorted.)
• Malfunction occurs in transfer control device drive circuit.
• Malfunction is detected in transfer shut off relay.TF-72, "Transfer Control Device"
Malfunction is detected in transfer shut off relay.TF-51, "Power Supply Circuit for
Transfer Control Unit"
ENGINE SPEED SIG
[P1820]• Malfunction is detected in engine speed signal that is output from
ECM through CAN communication.
• Improper signal is input while driving.TF-76, "Engine Speed Signal
(ECM)"
DUTY SOLENOID
[P1822]• Proper voltage is not applied to clutch pressure solenoid valve
due to open or short circuit.TF-76, "Clutch Pressure Sole-
noid"
2-4WD SOLENOID
[P1823]• Proper voltage is not applied to 2-4WD solenoid valve due to open
or short circuit.TF-80, "2-4WD Solenoid"
MOTOR RELAY
[P1824]• Motor does not operate properly due to open or short circuit in
transfer motor or motor relay.TF-84, "Transfer Motor"
OIL TEMP SEN
[P1826]• Signal voltage from fluid temperature sensor is abnormally high
(Transfer fluid temperature is abnormally low) while driving.TF-90, "Transfer Fluid Tempera-
ture"
CLUTCH PRES SW
[P1827]• Improper signal from clutch pressure switch is input due to open or
short circuit.
• Malfunction occurs in clutch pressure switch or hydraulic circuit.TF-92, "Clutch Pressure Switch"
LINE PRES SW
[P1828]• Improper signal from line pressure switch is input due to open or
short circuit.
• Malfunction occurs in line pressure switch or hydraulic circuit.TF-94, "Line Pressure Switch"
THROTTLE POSI SEN
[P1829]• Malfunction is detected in accelerator pedal position signal that is
output from ECM through CAN communication.
• Signal voltage from accelerator pedal position sensor is abnormal-
ly high or low.TF-97, "Throttle Position Signal
(ECM)"
ABS OP SIG
[P1830]• Malfunction is detected in ABS operation signal that is output from
ABS actuator and electric unit (control unit) through CAN commu-
nication.TF-97, "ABS Operation Signal
(ABS)"
VDC OP SIG
[P1831]• Malfunction is detected in VDC operation signal that is output from
ABS actuator and electric unit (control unit) through CAN commu-
nication.TF-98, "VDC Operation Signal
(ABS)"
TCS OP SIG
[P1832]• Malfunction is detected in TCS operation signal that is output from
ABS through CAN communication.TF-98, "TCS Operation Signal
(ABS)"
CAN COMM CIRCUIT
[U1000]• Malfunction has been detected from CAN communication line.TF-99, "CAN Communication
Line"
NO DTC IS DETECTED.
FURTHER TESTING MAY
BE REQUIRED.• No NG item has been detected. — Items (CONSULT-II screen
terms)Diagnostic item is detected when... Check item

TROUBLE DIAGNOSIS
TF-45
< SERVICE INFORMATION >
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2. Start engine and select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE” on CONSULT-II screen to erase DTC memory.
CAUTION:
If memory cannot be erased, perform applicable diagnosis.
DATA MONITOR MODE
Operation Procedure
Refer to GI-36, "CONSULT-II Start Procedure".
Display Item List
×: Standard –: Not applicable
Monitored item (Unit)Monitor item selection
Remarks
ECU INPUT
SIGNALSMAIN
SIGNALSSELEC-
TION FROM
MENU
VHCL/S SEN·FR [km/h] or [mph]×–×Wheel speed calculated by ABS actuator and
electric unit (control unit).
Signal input with CAN communication line.
VHCL/S SEN·RR [km/h] or [mph]×–×Wheel speed calculated by TCM.
Signal input with CAN communication line.
ENGINE SPEED [rpm]×–×Engine speed calculated by ECM.
Signal input with CAN communication line.
THRTL POS SEN [V]×–×Accelerator pedal position (APP) sensor sig-
nal voltage is displayed.
Signal input with CAN communication line.
FLUID TEMP SE [V]×–×Transfer fluid temperature sensor signal volt-
age is displayed.
BATTERY VOLT [V]×–×Power supply voltage for transfer control unit.
2WD SWITCH [ON/OFF]×–×4WD shift switch status is displayed.
AUTO SWITCH [ON/OFF]×–×4WD shift switch status is displayed.
LOCK SWITCH [ON/OFF]×–×4WD shift switch status is displayed.
(LOCK means 4H of 4WD shift switch.)
4L SW [ON/OFF]×–×4WD shift switch status is displayed.
(4L means 4LO of 4WD shift switch.)
N POSI SW TF [ON/OFF]×–×Neutral-4LO switch signal status is displayed.
ATP SWITCH [ON/OFF]×–×ATP switch signal status is displayed.
WAIT DETCT SW [ON/OFF]×–×Wait detection switch status is displayed.
LINE PRES SW [ON/OFF]×–×Line pressure switch status is displayed.
CL PRES SW [ON / OFF]×–×Clutch pressure switch status is displayed.
N POSI SW AT [ON/OFF]זדN” position signal of A/T PNP switch status is
displayed.
Signal input with CAN communication line.
R POSI SW AT [ON/OFF]זדR” position signal of A/T PNP switch status is
displayed.
Signal input with CAN communication line.
P POSI SW AT [ON/OFF]זדP” position signal of A/T PNP switch status is
displayed.
Signal input with CAN communication line.
ABS OPER SW [ON/OFF]×–×ABS operation signal status is displayed.
Signal input with CAN communication line.
VDC OPER SW [ON/OFF]×–×VDC operation signal status is displayed.
Signal input with CAN communication line.
TCS OPER SW [ON/OFF]×–×TCS operation signal status is displayed.
Signal input with CAN communication line.