brake INFINITI QX56 2006 Factory Service Manual

SE-82
AUTOMATIC DRIVE POSITIONER
Revision: November 20092006 QX56
Removal and InstallationEIS004YN
Refer to ACC-3, "ACCELERATOR CONTROL SYSTEM" and BR-6, "BRAKE PEDAL" .

TF-4
PRECAUTIONS
Revision: November 20092006 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EDS002H3
The Supplemental Restraint System such as “AIR 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 whether 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 inoperative, 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 per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Transfer Assembly and Transfer Control Unit ReplacementEDS002H4
When replacing transfer assembly or transfer control unit, check the 4WD shift indicator lamp as follows.
1. Turn ignition switch “ON ”.
2. Check 4WD shift indicator lamp is turned ON for approx. 1 second.

If OK, the position between transfer assembly and transfer control unit is correct.

If NG, the position is different between transfer assembly and transfer control unit.
Adjust the position between transfer assembly and transfer control unit. Refer to TF-4, "
METHOD FOR
POSITION ADJUSTMENT" .
METHOD FOR POSITION ADJUSTMENT
1. Start engine. Run the engine for at least 10 seconds.
2. Stop vehicle and move A/T selector lever to “N” position with brake pedal depressed. Stay in "N" for at
least 2 seconds.
3. Turn 4WD shift switch to “2WD ” position. Stay in "2WD" for at least 2 seconds.
4. Turn ignition switch “ OFF”.
5. Start engine.
6. Erase self-diagnosis. Refer to TF-47, "
How to Erase Self-diagnostic Results" (with CONSULT-II) or TF-
53, "ERASE SELF-DIAGNOSIS" (without CONSULT-II).
7. Check 4WD shift indicator lamp. Refer to TF-32, "
CHECK BEFORE ENGINE IS STARTED" .
If 4WD shift indicator lamp does not indicate "2WD", install new transfer control unit and retry the above
check.
PrecautionsEDS002H5

Before connecting or disconnecting the transfer control
unit harness connector, turn ignition switch “OFF” and dis-
connect battery ground cable. Failure to do so may damage
the transfer control unit. Battery voltage is applied to trans-
fer control unit even if ignition switch is turned “OFF”.
SEF289H

TF-18
ALL-MODE 4WD SYSTEM
Revision: November 20092006 QX56
4WD mode. Setting the vehicle in the 2WD mode requires no pressure buildup. In other words, pressure force
applied to the wet-multiplate clutch becomes zero.
CLUTCH PRESSURE SOLENOID VALVE
The clutch pressure solenoid valve distributes torque (front and rear) in AUTO mode.
LINE PRESSURE SWITCH

With the transfer system design, control of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.

The line pressure switch determines whether or not adequate line pressure has built up under different
operating conditions.

The line pressure switch turns ON when line pressure is produced.

The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH

The clutch pressure switch determines whether or not adequate clutch pressure has built up under differ-
ent operating conditions.

The clutch pressure switch turns ON when clutch pressure is produced.

The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
TRANSFER FLUID TEMPERATURE SENSOR
The transfer temperature sensor detects the transfer fluid temperature and sends a signal to the transfer con-
trol unit.
TRANSFER CONTROL UNIT

Transfer control unit controls transfer control device by input signals of each sensor and each switch.

Self-diagnosis can be done.
TRANSFER CONTROL DEVICE
The transfer control device changes the state of transfer assembly between 2WD, AUTO, 4H⇔4LO with the
2WD, AUTO, 4H and 4LO signals of 4WD shift switch.
NOTE:

To shift between 4H ⇔4LO, stop the vehicle, depress the brake pedal and shift the transmission selector
to the "N" position. Depress and turn the 4WD shift switch. The shift switch will not shift to the desired
mode if the transmission is not in "N" or the vehicle is moving. The 4LO indicator lamp will be lit when the
4LO is engaged.

Actuator motor and actuator position switch are integrated.
4WD SHIFT SWITCH AND INDICATOR LAMP
4WD Shift Switch
The 4WD shift switch allows selection from 2WD, AUTO, 4H or 4LO.
4WD Shift Indicator Lamp

Displays driving conditions selected by 4WD shift switch with 2WD, AUTO and 4H indicators while engine
is running. (When 4WD warning lamp is turned on, all 4WD shift indicator lamps are turned off.)

Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4LO Indicator Lamp

Displays 4LO condition while engine is running. 4LO indicator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H ⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)

Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.

TF-32
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Inspections Before Trouble DiagnosisEDS002HH
TRANSFER FLUID CHECK
Check fluid for leaks and fluid level. Refer to TF-11, "Inspection" .
PREPARATION FOR ROAD TEST

The purpose of the test is to determine overall performance of
transfer and analyze causes of problems.

When a malfunction is found in any part of transfer, perform the
road test to locate the malfunction area and repair the malfunc-
tion parts.

The road test consists of the following three parts.
–Check before engine is started. Refer to TF-32, "CHECK
BEFORE ENGINE IS STARTED" .
–Check at idle. Refer to TF-32, "CHECK AT IDLE" .
–Cruise test. Refer to TF-33, "CRUISE TEST" .
CHECK BEFORE ENGINE IS STARTED
1. CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface.
2. Turn ignition switch to “OFF ” position.
3. Move A/T selector lever to “P ” position.
4. Set 4WD shift switch to “2WD” position.
5. Turn ignition switch to “ON ” position. (Do not start engine.)
Does 4WD shift indicator lamp turn ON for approximately 1 second?
YES >> GO TO 2.
NO >> Go to TF-117, "
4WD Shift Indicator Lamp and 4LO Indicator Lamp Do Not Turn ON" .
2. CHECK 4WD WARNING LAMP
1. Turn ignition switch to “OFF ” position.
2. Move A/T selector lever to “P ” position.
3. Set 4WD shift switch to “2WD” position.
4. Turn ignition switch to “ON ” position. (Do not start engine.)
Does 4WD warning lamp turn ON?
YES >> GO TO TF-32, "CHECK AT IDLE" .
NO >> GO TO TF-121, "
4WD Warning Lamp Does Not Turn ON" .
CHECK AT IDLE
1. CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface and engage the parking brake.
2. Turn ignition switch to “OFF ” position.
3. Move A/T selector lever to “P ” position.
4. Set 4WD shift switch to “2WD” position.
5. Start engine.
Does 4WD shift indicator lamp turn ON?
YES >> GO TO 3.
NO >> GO TO 2.
SMT089D

TROUBLE DIAGNOSISTF-33
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Revision: November 2009 2006 QX56
2. CHECK 4WD WARNING LAMP
Check 4WD warning lamp state?
Is 4WD warning lamp turned ON?
YES >> Perform the self-diagnosis. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CON-
SULT-II)" (with CONSULT-II) or TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITHOUT CON-
SULT-II)" (without CONSULT-II).
NO >> Go to TF-123, "
4WD Shift Indicator Lamp or 4LO Indicator Lamp Does Not Change" .
3. CHECK 4WD SHIFT INDICATOR AND 4LO INDICATOR OPERATION
1. Brake pedal depressed.
2. Move A/T selector lever to “N” position.
3. Set 4WD shift switch to “2WD”, “AUTO ”, “4H ”, “4LO ”, “4H ”,
“AUTO ” and “2WD” in order. (Stay at each switch position for at
least 1 second.)
Do 4WD shift indicator and 4LO indicator lamps change properly?
Does buzzer sound?
YES >> GO TO TF-33, "CRUISE TEST" .
NO >> GO TO TF-123, "
4WD Shift Indicator Lamp or 4LO Indi-
cator Lamp Does Not Change" .
CRUISE TEST
1. CHECK INPUT SIGNAL
1. Warm up engine to normal operating temperature.
2. Park vehicle on flat surface.
3. Move A/T selector lever to “P” position.
4. Set 4WD shift switch to “AUTO” position.
5. Start engine.
6. Drive vehicle for at least 30 seconds at a speed higher than 20 km/h (12 MPH).
Check 4WD warning lamp turned ON?
On steady>>Perform the self-diagnosis. Refer to TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITH CON-
SULT-II)" (with CONSULT-II) or TF-50, "SELF-DIAGNOSTIC PROCEDURE (WITHOUT CON-
SULT-II)" (without CONSULT-II).
Flash rapidly>>GO TO TF-128, "
4WD Warning Lamp Flashes Rapidly" .
Flash slowly>>GO TO TF-129, "
4WD Warning Lamp Flashes Slowly" .
NO >> GO TO 2.
WDIA0136E

TF-36
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
LOCK SWITCH [ON/
OFF]Input condition from
4WD shift switch 4WD shift switch: 4H
ON
4WD shift switch: 2WD, AUTO or 4LO OFF
4L SWITCH [ON/OFF] Input condition from
4WD shift switch 4WD shift switch: 4LO
ON
4WD shift switch: 2WD, AUTO or 4H OFF
N POSI SW TF [ON/
OFF] Condition of neutral-4LO
switch

Vehicle stopped

Engine running

A/T selector lever
“N ” posi-
tion

Brake pedal depressed 4WD shift switch: 2WD,
AUTO or 4H
OFF
4WD shift switch: 4H to
4LO (While actuator
motor is operating.) OFF
→ ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.) ON
→ OFF
4WD shift switch: 4LO ON
ATP SWITCH [ON/OFF] Condition of ATP switch

Vehicle stopped

Engine running

A/T selector lever “N ”

Brake pedal depressed 4WD 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 depressed 4WD shift switch: 2WD,
AUTO or 4H
OFF
4WD shift switch: 4H to
4LO (While actuator
motor 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 4H ON

Except the above

The vehicle has been left
at room temperature for 5
minutes and more with
ignition switch in “
OFF”
position.
Ignition switch: ON

A/T selector lever: “P ”
or "N" position

4WD shift switch: other
than AUTO OFF
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
operating.) 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 depressed A/T selector lever posi-
tion: N
ON
Except the above OFF
R POSI SW AT [ON/
OFF] Input condition from A/T
PNP switch

Vehicle stopped

Engine running

Brake pedal depressed A/T selector lever posi-
tion: R
ON
Except the above OFF
Monitored item [Unit]
Content ConditionDisplay value

TROUBLE DIAGNOSISTF-37
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Revision: November 2009 2006 QX56
P POSI SW AT [ON/
OFF]Input condition from A/T
PNP switch
Vehicle stopped

Engine running

Brake pedal depressed A/T selector lever posi-
tion: P
ON
Except the above OFF
ABS OPER SW [ON/
OFF] Condition of ABS operat-
ing ABS is operating.
ON
ABS is not operating. OFF
VDC OPER SW [ON/
OFF] Condition of VDC operat-
ing VDC is operating.
ON
VDC is not operating. OFF
TCS OPER SW [ON/
OFF] Condition of TCS operat-
ing TCS is operating.
ON
TCS is not operating. OFF
THROTTLE POSI [0.0/8] Condition of throttle
opening When 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 depressed 4WD shift switch: 2WD
2WD
4WD shift switch: AUTO AUTO
4WD shift switch: 4H LOCK
4WD shift switch: 4LO 4L
VHCL/S COMP [km/h] or
[mph] Vehicle speed Vehicle stopped
0 km/h (0 MPH)
Vehicle running
CAUTION:
Check air pressure of tire under standard condition. Approximately
equal to the indi-
cation on speed-
ometer (Inside of
±
10%)
COMP CL TORQ [kgm] Condition of control
torque

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 2WD 0 kg-m
4WD shift switch: AUTO
39 - 1,353 N
·m
(4 - 138 kg-m, 29 - 998 ft-lb)
4WD shift switch: 4H or
4LO 1,353 N
·m
(138 kg-m, 998 ft- lb)
DUTY SOLENOID [%] Condition of clutch pres-
sure solenoid

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 2WD
4%
4WD shift switch: AUTO 96 - 4%
4WD shift switch: 4H or
4LO 4%
2-4WD SOL [ON/OFF] Condition of 2-4WD shift
solenoid valve

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 2WD
OFF
4WD shift switch: AUTO ON
4WD shift switch: 4H
4WD shift switch: 4LO
4WD shift switch: AUTO
( “ Wait ” function is operat-
ing.) OFF
4WD shift switch: 4H
( “ Wait ” function is operat-
ing.) OFF
Monitored item [Unit]
Content ConditionDisplay value

TF-38
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
2-4WD SOL MON [ON/
OFF]Check signal for transfer
control unit signal output

Vehicle stopped

Engine running

A/T selector lever
“N ” posi-
tion

Brake pedal depressed 4WD shift switch: 2WD
OFF
4WD shift switch: AUTO ON
4WD shift switch: 4H
4WD shift switch: 4LO
4WD shift switch: AUTO
( “ Wait ” function is operat-
ing.) OFF
4WD shift switch: 4H
( “ Wait ” function is operat-
ing.) OFF
MOTOR RELAY [ON/
OFF] Condition of transfer
motor relay

Accelerator pedal
depressed

Vehicle stopped

Engine running

Brake pedal depressed 4WD shift switch: 2WD
OFF
4WD shift switch: AUTO
or 4LO (A/T selector lever
“ P ” or “N ” position) OFF
("ON" for approx. 2
sec. after shifting to “P ” and “ N”.)
4WD shift switch: AUTO
or 4LO (Except for A/T
selector lever “P ” or “ N”
position) ON
4WD shift switch: 4H (A/T
selector lever “P ” posi-
tion) OFF
("ON" for approx. 2 sec. after shifting to “P”.)
4WD shift switch: 4H
(Except for A/T selector
lever “P ” position) ON
MOTOR RELAY MON
[ON/OFF] Check signal for transfer
control unit signal output

Accelerator pedal
depressed

Vehicle stopped

Engine running

Brake pedal depressed 4WD shift switch: 2WD OFF
4WD shift switch: AUTO
or 4LO (A/T selector lever
“
P ” or “N ” position) OFF
("ON" for approx. 2
sec. after shifting to “P ” and “ N”.)
4WD shift switch: AUTO
or 4LO (Except for A/T
selector lever “P ” or “ N”
position) ON
4WD shift switch: 4H (A/T
selector lever “P ” posi-
tion) OFF
("ON" for approx. 2
sec. after shifting to “P”.)
4WD shift switch: 4H
(Except for A/T selector
lever “P ” position) ON
4WD FAIL LAMP [ON/
OFF] Condition of 4WD warn-
ing lamp 4WD warning lamp: ON
ON
4WD warning lamp: OFF OFF
2WD IND [ON/OFF] Condition of 4WD shift
indicator lamp (2WD
indicator lamp) 2WD indicator lamp of 4WD shift indicator lamp: OFF
OFF
2WD indicator lamp of 4WD shift indicator lamp: ON ON
AUTO IND [ON/OFF] Condition of 4WD shift
indicator lamp (AUTO
indicator lamp) AUTO indicator lamp of 4WD shift indicator lamp: OFF
OFF
AUTO indicator lamp of 4WD shift indicator lamp: ON ON
LOCK IND [ON/OFF] Condition of 4WD shift
indicator lamp (Lock indi-
cator lamp) Lock indicator lamp of 4WD shift indicator lamp: OFF
OFF
Lock indicator lamp of 4WD shift indicator lamp: ON ON
4L IND [ON/OFF] Condition of 4LO indica-
tor lamp condition 4LO indicator lamp: OFF
OFF
4LO indicator lamp: ON ON
Monitored item [Unit]
Content ConditionDisplay value

TROUBLE DIAGNOSISTF-39
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Revision: November 2009 2006 QX56
Specifications Between Transfer Control Unit Terminals
TRANSFER CONTROL UNIT TERMINAL CONNECTOR LAYOUT
ATP IND [ON/OFF]Condition of ATP indica-
tor lamp ATP indicator lamp: ON
ON
ATP indicator lamp: OFF OFF
SHIFT POS SW1 [ON/
OFF] Condition of actuator
position switch 1
(Low)

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 4LO
ON
4WD shift switch: 2WD,
AUTO or 4H OFF
SHIFT POS SW2 [ON/
OFF] Condition of actuator
position switch 2
(High)

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 4H,
AUTO or 2WD
ON
4WD shift switch: 4LO OFF
SHIFT ACT1 [ON/OFF] Output condition to actu-
ator motor (High)

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 4H to
4LO (
“Wait ” function is
operating.) ON
Except the above OFF
SHIFT AC MON1 [ON/
OFF] Check signal for transfer
control unit signal output

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 4H to
4LO (
“Wait ” function is
operating.) ON
Except the above OFF
SHIFT ACT2 [ON/OFF] Output condition to actu-
ator motor (Low)

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 4LO to
4H (
“Wait ” function is
operating.) ON
Except the above OFF
SHIFT AC MON2 [ON/
OFF] Check signal for transfer
control unit signal output

Vehicle stopped

Engine running

A/T selector lever “
N” posi-
tion

Brake pedal depressed 4WD shift switch: 4LO to
4H (
“Wait ” function is
operating.) ON
Except the above OFF
T/F F SPEED [km/h] or
[mph] Displayed, but do not use.
A/T R SPEED [km/h] or
[mph] Condition of vehicle
speed sensor A/T (Revo-
lution sensor)
During driving Approximately
matches the out-
put shaft speed.
AT GEAR POSI [1/2/3/4/
5] Condition of A/T selec-
tor lever position
Displays actual A/T gear position.
1/2/3/4/5
Monitored item [Unit]
Content ConditionDisplay value
WDIA0204E

TF-40
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
NOTE:
Data are reference value and are measured between each terminal and ground.
Te r m i n a lWire
color Item
ConditionData (Approx.)
1 GR 2-4WD shift solenoid valve

Vehicle stopped

Engine running

A/T selector lever
“ N ” position

Brake pedal
depressed 4WD shift switch: 2WD
0V
4WD shift switch: AUTO, 4H or 4LO Battery voltage
2 B/W 4WD shift indicator lamp
(2WD indicator lamp) 2WD indicator lamp: OFF
Battery voltage
2WD indicator lamp: ON 0V
3 B Ground Always0V
4 Y/L Transfer shift high relay

Vehicle stopped

Engine running

A/T selector lever
“ N ” position

Brake pedal
depressed 4WD shift switch: 4H to 4LO (
“Wait ” func-
tion is operating.) Battery voltage
Except the above 0V
5 W/B 4WD warning lamp 4WD warning lamp: ON
0V
4WD warning lamp: OFF Battery voltage
6 B Ground Always0V
7 L CAN-H ——
8 P CAN-L ——
9G/W 4WD shift switch
(2WD) Ignition switch: ON4WD shift switch: 2WD
Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
10 L/W Transfer dropping resistor

Vehicle stopped

Engine running

A/T selector lever
“ N ” position

Brake pedal
depressed 4WD shift switch: AUTO 4 - 14V
4WD shift switch: 2WD, 4H or 4LO Less than 1V
11 L 4WD shift indicator lamp
(Lock indicator lamp) Lock indicator lamp of 4WD shift indicator lamp: OFF
Battery voltage
Lock indicator lamp of 4WD shift indicator lamp: ON 0V
12 W/G 4LO indicator lamp 4LO indicator lamp: OFF
Battery voltage
4LO indicator lamp: ON 0V
13 G/B Transfer shift low relay

Vehicle stopped

Engine running

A/T selector lever
“ N ” position

Brake pedal
depressed 4WD shift switch: 4LO to 4H (
“Wait ” func-
tion is operating.) Battery voltage
Except the above 0V