2010 INFINITI QX56 tires

OVERHEATING CAUSE ANALYSISCO-9
< FUNCTION DIAGNOSIS >
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Except cool-
ing system
parts mal-
function —
Overload on engine Abusive driving
High engine rpm under no
load
Driving in low gear for ex-
tended time
Driving at extremely high
speed
Powertrain system malfunc-
tion
—
Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flow Blocked radiator grille Installed car brassiere
—
Mud contamination or paper
clogging
Blocked bumper
Blocked radiator
Blocked condenser
Blocked air flow
Installed large fog lamp
Symptom
Check items
Revision: April 20092010 QX56

DLN-10
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
FUNCTION DIAGNOSIS
4WD SYSTEM
System DiagramINFOID:0000000005148770
COMPONENT DESCRIPTION
WDIA0164E
Components
Function
Transfer control unit Controls transfer control device, control valves and shifts between 2WD/4WD and 4H/4LO.
Transfer control device Integrates actuator motor and actuator position switch.
2-4WD shift solenoid valve Controls oil pressure and allows shifting between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque between front and rear tires.
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sensor Detects transfer fluid temperature.
Actuator motor Moves shift rods when signaled by transfer control unit.
Actuator position switch Detects actuator motor position.
Wait detection switch Detects whether or not 4WD lock gear is locked.
4LO switch Detects if transfer case is in 4LO.
ATP switch Detects if transfer case is in neutral.
4WD shift switch Allows driver to select from 2WD/4WD, 4H/4LO and AUTO.
4WD warning lamp • Illuminates if malfunction is detected in 4WD system.
• Flashes (1 flash / 2 seconds) if large difference in diameter of front and rear tires.
• Flashes (2 flashes / 1 second) if high transfer fluid temperature is detected.
AT P w a r n i n g l a m p Indicates that A/T parking mechanism does not operate when A/T selector lever is in P position
because transfer case is in neutral.
4WD shift indicator lamp Displays driving range selected by 4WD shift switch.
4LO indicator lamp Displays 4LO range.
Revision: April 20092010 QX56

DLN-14
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
• 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.
4WD WARNING LAMP
Turns on or flashes when there is a malfunction in 4WD system.
Also turns on when ignition switch is turned ON, for purpose of lamp che\
ck. Turns OFF approximately 1 sec-
ond after the engine starts if system is normal.
4WD Warning Lamp Indication
ATP WARNING LAMP
When the A/T selector lever is in P position, the vehicle may move if the transfer case is in neutral. ATP warn-
ing lamp is turned on to indicate this condition to the driver.
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 oper- ating conditions.
• The line pressure switch closes 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 different
operating conditions.
• The clutch pressure switch closes when clutch pressure is produced.
• The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
WAIT DETECTION SWITCH
• The wait detection switch operates when there is circulating torque produced in the propeller shaft (L→H) or
when there is a phase difference between 2-4 sleeve and clutch drum (H →L). After the release of the circu-
lating torque, the wait detection switch helps provi de the 4WD lock gear (clutch drum) shifts. A difference
may occur between the operation of the 4WD shift swit ch and actual drive mode. At this point, the wait
detection switch senses an actual drive mode.
• The wait detection switch operates as follows.
- 4WD lock gear (clutch drum) locked: ON
- 4WD lock gear (clutch drum) released: OFF
• The wait detection switch senses an actual drive mode and the 4WD shift indicator lamp indicates the vehi-
cle drive mode.
ATP SWITCH
ATP switch detects if transfer case is in neutral by the position of the L-H shift fork.
NOTE:
Transfer case may be in neutral when shifting between 4H-4LO.
NEUTRAL-4LO SWITCH
The neutral-4LO switch detects that transfer gear is in neutral or 4LO (or shifting from neutral to 4LO) condi-
tion by L-H shift fork position.
Condition 4WD warning lamp
System normal OFF
Lamp check Turns ON when ignition switch is turned ON.
Turns OFF after engine start.
4WD system malfunction ON
During self-diagnosis Flashes malfunction mode.
Large difference in diameter of front/
rear tires Flashes slow (1 flash / 2 seconds)
(Continues to flash until the ignition switch is turned OFF)
High fluid temperature in transfer case Flashes rapidly (2 flashes / 1 second)
(Continues to flash until fluid temperature returns to normal)
Revision: April 20092010 QX56

DLN-112
< SYMPTOM DIAGNOSIS >[ATX14B]
4WD WARNING LAMP FLASHES RAPIDLY
4WD WARNING LAMP FLASHES RAPIDLY
DescriptionINFOID:0000000005148867
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:0000000005148868
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-68, "
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: April 20092010 QX56

4WD WARNING LAMP FLASHES SLOWLYDLN-113
< SYMPTOM DIAGNOSIS > [ATX14B]
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4WD WARNING LAMP FLASHES SLOWLY
DescriptionINFOID:0000000005148869
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:0000000005148870
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-68, "
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-71, "
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: April 20092010 QX56

DLN-184
< SYMPTOM DIAGNOSIS >[PROPELLER SHAFT: 2F1310]
NOISE, VIBRATION, AND HARSHNESS
(NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000005148899
Use the chart below to help you find the cause of the sy mptom. If necessary, repair or replace these parts.
×: ApplicableReference page
DLN-185, "
On-Vehicle Service
"
DLN-185, "
On-Vehicle Service
"
DLN-185, "
On-Vehicle Service
"
DLN-208, "
NVH Troubleshooting Chart
"
RAX-5, "
NVH Troubleshooting Chart
"
RSU-5, "
NVH Troubleshooting Chart
"
WT-43, "
NVH Troubleshooting Chart
"
WT-43, "
NVH Troubleshooting Chart
"
RAX-10, "
Removal and Installation
"
BR-6, "
NVH Troubleshooting Chart
"
ST-12, "
NVH Troubleshooting Chart
"
Possible cause and suspected parts
Uneven rotation torque
Rotation imbalance
Excessive run out
Differential
Axle
Suspension
Tires
Road wheel
Drive shaft
Brakes
Steering
Symptom Noise
×××××××××××
Shake ×××××××
Vibration ××××××××
Revision: April 20092010 QX56

DLN-194
< SYMPTOM DIAGNOSIS >[PROPELLER SHAFT: 2S1410]
NOISE, VIBRATION, AND HARSHNESS
(NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION, AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000005148906
Use the chart below to help you find the cause of the sy mptom. If necessary, repair or replace these parts.
×: ApplicableReference page
DLN-195, "
On-Vehicle Service
"
DLN-195, "
On-Vehicle Service
"
DLN-195, "
On-Vehicle Service
"
DLN-242, "
NVH Troubleshooting Chart
"
RAX-5, "
NVH Troubleshooting Chart
"
RSU-5, "
NVH Troubleshooting Chart
"
WT-43, "
NVH Troubleshooting Chart
"
WT-43, "
NVH Troubleshooting Chart
"
RAX-5, "
NVH Troubleshooting Chart
"
BR-6, "
NVH Troubleshooting Chart
"
ST-12, "
NVH Troubleshooting Chart
"
Possible cause and suspected parts
Uneven rotation torque
Rotation imbalance
Excessive run out
Differential
Axle
Suspension
Tires
Road wheel
Drive shaft
Brakes
Steering
Symptom Noise
×××××××××××
Shake ×××××××
Vibration ××××××××
Revision: April 20092010 QX56

DLN-208
< SYMPTOM DIAGNOSIS >[FRONT FINAL DRIVE: M205]
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING
SYMPTOM DIAGNOSIS
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting ChartINFOID:0000000005148915
Use the chart below to help you find the cause of the sy mptom. If necessary, repair or replace these parts.
×: ApplicableReference page
DLN-217, "
Disassembly and Assembly
"
DLN-217, "
Disassembly and Assembly
"
DLN-217, "
Disassembly and Assembly
"
DLN-234, "
Inspection and Adjustment
"
DLN-217, "
Disassembly and Assembly
"
DLN-209, "
Checking Front Differential Gear Oil
"
DLN-184, "
NVH Troubleshooting Chart
"
FA X - 5 , "
NVH Troubleshooting Chart
"
FSU-5, "
NVH Troubleshooting Chart
"
WT-43, "
NVH Troubleshooting Chart
"
WT-43, "
NVH Troubleshooting Chart
"
FA X - 5 , "
NVH Troubleshooting Chart
"
BR-6, "
NVH Troubleshooting Chart
"
ST-12, "
NVH Troubleshooting Chart
"
Possible cause and SUSPECTED PARTS
Gear tooth rough
Gear contact improper
Tooth surfaces worn
Incorrect backlash
Companion flange excessive runout
Gear oil improper
PROPELLER SHAFT
FRONT AXLE
FRONT SUSPENSION
TIRES
ROAD WHEEL
DRIVE SHAFT
BRAKES
STEERING
Symptom
Noise××××××××××××××
Revision: April 20092010 QX56