ignition INFINITI QX56 2009 Factory Service Manual

DLN-110
< SYMPTOM DIAGNOSIS >[ATX14B]
ATP WARNING LAMP DOES NOT TURN ON
- Transfer control unit harness
connector E143 (B) terminal 40
and combination meter harness connector M23 (A) terminal 44.
Also check harness for short to ground and short to power.
Are the inspection results normal?
YES >> GO TO 6.
NO >> Repair or replace damaged parts.
6.CHECK ATP WARNING LAMP CIRCUIT
1. Place A/T selector lever in P position.
2. Connect combination meter harness connector and transfer control unit harness connector.
3. Disconnect ATP switch harness connector.
4. Ground the following terminal using suitable wiring.
- ATP switch harness connector F55 terminal 8 and ground.
5. Turn ignition switch ON. (Do not start engine.)
Does indicator lamp turn on?
YES >> GO TO 7.
NO >> Replace combination meter. Refer to MWI-102,
"Removal and Installation".
7.SYMPTOM CHECK
Check again.
Are the inspection results normal?
YES >> Inspection End.
NO >> GO TO 8.
8.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "Reference Value"
.
Are the inspection results normal?
YES >> GO TO 9.
NO >> Check transfer control unit pin terminals fo r damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
9.CHECK TRANSFER INNER PARTS
1. Disassemble transfer assembly. Refer to DLN-142, "Disassembly and Assembly"
.
2. Check transfer inner parts.
Are the inspection results normal?
YES >> Inspection End.
NO >> Repair or replace damaged parts. 40 to 44: Continuity should not exist.
44 to 40: Continuity should exist.
AWDIA0186ZZ
SDIA2769E
Revision: December 20092009 QX56

DLN-112
< SYMPTOM DIAGNOSIS >[ATX14B]
4WD WARNING LAMP FLASHES RAPIDLY
4WD WARNING LAMP FLASHES RAPIDLY
DescriptionINFOID:0000000003772172
The 4WD warning lamp flashes quickly while driving (2 times / second). The lamp continues to flash until the
ignition switch is turned OFF.
Diagnosis ProcedureINFOID:0000000003772173
1.CHECK TIRE
Check the following.
 Tire pressure
 Wear condition
 Longitudinal tire size (There is no difference between longitudinal tires.)
Are the inspection results normal?
YES >> GO TO 2.
NO >> Repair or replace damaged parts.
2.CHECK 4WD WARNING LAMP
Stop the vehicle and allow it to idle for a short period of time.
Does flashing stop?
YES >> Inspection End.
NO >> GO TO 3.
3.CHECK TRANSFER FLUID TEMPERATURE
Perform trouble diagnosis for transfer fluid temperature system. Refer to DLN-67, "Diagnosis Procedure"
.
Are the inspection results normal?
YES >> GO TO 4.
NO >> Repair or replace damaged parts.
4.SYMPTOM CHECK
Check again.
Are the inspection results normal?
YES >> Inspection End.
NO >> GO TO 5.
5.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "Reference Value"
.
Are the inspection results normal?
YES >> Inspection End.
NO >> Check transfer control unit pin terminals fo r damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
Revision: December 20092009 QX56

4WD WARNING LAMP FLASHES SLOWLYDLN-113
< SYMPTOM DIAGNOSIS > [ATX14B]
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4WD WARNING LAMP FLASHES SLOWLY
DescriptionINFOID:0000000003772174
The 4WD warning lamp flashes slowly while driving (1 ti me / 2 seconds). The lamp continues to flash until the
ignition switch is turned OFF.
Diagnosis ProcedureINFOID:0000000003772175
1.CHECK TIRE
Check the following.
 Tire pressure
 Wear condition
 Longitudinal tire size (There is no difference between longitudinal tires.)
OK or NG
OK >> GO TO 2.
NG >> Repair or replace damaged parts.
2.CHECK TRANSFER FLUID TEMPERATURE
Perform trouble diagnosis for transfer fl uid temperature system. Refer to DLN-67, "Diagnosis Procedure"
.
Are the inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK CLUTCH PRESSURE SWITCH
Perform trouble diagnosis for clutch pr essure switch system. Refer to DLN-70, "Diagnosis Procedure"
.
Are the inspection results normal?
YES >> GO TO 4.
NO >> Repair or replace damaged parts.
4.SYMPTOM CHECK
Check again.
Are the inspection results normal?
YES >> Inspection End.
NO >> GO TO 5.
5.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "Reference Value"
.
Are the inspection results normal?
YES >> Inspection End.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
Revision: December 20092009 QX56

DLN-116
< SYMPTOM DIAGNOSIS >[ATX14B]
ATP SWITCH
ATP SWITCH
DescriptionINFOID:0000000003772178
The ATP indicator is ON when the transfer case is not in neutral.
Diagnosis ProcedureINFOID:0000000003772179
DIAGNOSTIC PROCEDURE
1.CHECK ATP SWITCH SIGNAL

With CONSULT-III
1. Start engine.
2. Select DATA MONITOR mode for A LL MODE AWD/4WD with CONSULT-III.
3. Read out the value of ATP SWITCH.
Without CONSULT-III
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Are inspection results normal?
YES >> GO TO 5.
NO >> GO TO 2.
2.CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND ATP SWITCH
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness c onnector and the ATP switch harness connector.
3. Check continuity between transfer control unit harness connec- tor E143 terminal 40 and ATP switch harness connector F55 ter-
minal 8.
Also check harness for short to ground and short to power.
Are inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK GROUND CIRCUIT
Condition Display value
 Vehicle stopped
 Engine running
 A/T selector lever N
 Brake pedal de- pressed 4WD shift switch
: 4H to 4LO or 4LO to 4H
(While actuator motor is operating.)
ON
Except the above OFF
Connector Terminal Condition Voltage
(Approx.)
E143 40 -
Ground  Vehicle stopped
 Engine running
 A/T selector lever
N
 Brake pedal de- pressed 4WD shift switch: 4H
to 4LO or 4LO to 4H
(While actuator motor
is operating.)
0V
Except the above Battery
voltage
SDIA2755E
Continuity should exist.
SDIA2756E
Revision: December 20092009 QX56

ATP SWITCHDLN-117
< SYMPTOM DIAGNOSIS > [ATX14B]
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1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect ATP switch harness connector.
3. Check continuity between ATP switch harness connector F55 terminal 9 and ground.
Also check harness for short to ground and short to power.
Are inspection results normal?
YES >> GO TO 4.
NO >> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK ATP SWITCH
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect ATP switch harness connector.
3. Remove ATP switch. Refer to DLN-16, "Component Parts Location"
.
4. Push and release ATP switch and check continuity between ATP
switch terminals 8 and 9.
Are inspection results normal?
YES >> GO TO 5.
NO >> Replace ATP switch.
5.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "Reference Value"
.
Are inspection results normal?
YES >> GO TO 6.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
6.CHECK ATP WARNING LAMP
1. Turn ignition switch ON. (Do not start engine.)
2. Move A/T selector lever to P position.
3. Set 4WD shift switch from 4H to 4LO or 4LO to 4H.
Does ATP warning lamp turn ON while switching?
YES >> Inspection End.
NO >> GO TO DLN-109, "Diagnosis Procedure"
.
Continuity should exist.
SDIA2394E
Terminal Condition Continuity
8 - 9 Push ATP switch Yes
Release ATP switch No
SDIA2757E
Revision: December 20092009 QX56

DLN-120
< PRECAUTION >[ATX14B]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint S
ystem (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005874977
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 SR and SB section of this Service Man-
ual.
WARNING:
 To avoid rendering the SRS inopera tive, 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 NISS AN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
 Do not use electrical test equipmen t 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.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
 When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005874978
NOTE:
 This Procedure is applied only to models with Intelli gent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
 Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: December 20092009 QX56

PRECAUTIONSDLN-121
< PRECAUTION > [ATX14B]
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5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
Precaution for Transfer Assembly and Transfer Control Unit ReplacementINFOID:0000000004193517
When replacing transfer assembly or transfer control uni t, check the 4WD shift indicator lamp as follows.
1. Turn ignition switch ON.
2. Check 4WD shift indicator lamp is turned ON for approximately 1 second.
 If OK, the position between transfer assemb ly 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. See METHOD FOR POSITION
ADJUSTMENT that follows.
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 DLN-18, "CONSULT-III Function (ALL MODE AWD/4WD)"
.
7. Check 4WD shift indicator lamp. Refer to DLN-7, "Preliminary Check"
.
If 4WD shift indicator lamp does not indicate 2WD, install new transfer control unit and retry the above
check.
PrecautionINFOID:0000000004193518
 Before connecting or disconnect ing the transfer control unit
harness connector, turn ignition switch “OFF” and disconnect
battery cables. Failure to do so may damage the transfer con-
trol unit. Battery voltage is ap plied to transfer control unit
even if ignition swit ch is turned “OFF”.
 When connecting or disconnect ing pin connectors into or
from transfer control unit, take care not to damage pin termi-
nals (bend or break).
When connecting pin connectors make sure that there are not
any bends or breaks on transfer control unit pin terminals.
SEF289H
SEF291H
Revision: December 20092009 QX56

DLN-130
< ON-VEHICLE REPAIR >[ATX14B]
TRANSFER CONTROL UNIT
ON-VEHICLE REPAIR
TRANSFER CONTROL UNIT
Removal and InstallationINFOID:0000000004193525
REMOVAL
1. Set transfer state as 2WD when 4WD shift switch is
at 2WD, or as AUTO when 4WD shift switch is at
AUTO.
CAUTION:
When removing transfer co ntrol unit, transfer state must be at 2WD or AUTO.
2. Turn the ignition switch OFF and disconnect negative battery terminal.
3. Remove the lower instrument panel RH. Refer to IP-17, "Exploded View"
.
4. Disconnect the two transfer control unit connectors.
5. Remove the transfer control unit bolts.
6. Remove the transfer control unit.
INSTALLATION
Installation is in the reverse order of removal.
 When installing the transfer control unit, tighten bolts to the specified torque.
CAUTION:
Do not connect harness connector to transfer control unit when 4WD shift switch is at 4LO.
 After the installation, check perform self-diagnosis. Refer to DLN-6, "Work Flow"
. If NG, adjust position
between transfer assembly and transfer control unit. Refer to DLN-121, "Precaution for Transfer Assembly
and Transfer Control Unit Replacement".
BDIA0014E
Transfer control unit bolts : 3.4 N·m (0.35 kg-m, 30 in-lb)
Revision: December 20092009 QX56

PRECAUTIONSDLN-181
< PRECAUTION > [PROPELLER SHAFT: 2F1310]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005875025
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 whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR 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 SR 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.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
 When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution Necessary for Steering Wh eel Rotation After Battery Disconnect
INFOID:0000000005875026
NOTE:
 This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
 Remove and install all control units after disconnecti ng both battery cables with the ignition knob in the
″ LOCK ″ position.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS , an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
Revision: December 20092009 QX56

DLN-182
< PRECAUTION >[PROPELLER SHAFT: 2F1310]
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Revision: December 20092009 QX56