2008 INFINITI QX56 ESP

DLK-200
< SYMPTOM DIAGNOSIS >[WITH INTELLIGENT KEY SYSTEM]
INTELLIGENT KEY SYSTEM SYMPTOMS
SYMPTOM DIAGNOSIS
INTELLIGENT KEY SYSTEM SYMPTOMS
Symptom TableINFOID:0000000001539065
ALL FUNCTIONS OF INTELLIGENT KEY SYSTEM DO NOT OPERATE
NOTE:
• Before performing the diagnosis in the following table, check “WORK FLOW”. Refer to
DLK-6, "
Work Flow".
• Check that vehicle is under the condition shown in “Conditions of vehicle” before starting diagnosis, and
check each symptom.
• If the following symptoms are detected, check syst ems shown in the “Diagnosis/service procedure” column
in this order.
Conditions of Vehicle (Operating Conditions)
• “ENGINE START BY I-KEY” and “LOCK/UNLOCK BY I-KEY” are ON when se tting on CONSULT-III.
• All doors are closed.
Symptom Diagnosis/service procedureReference page
All doors and ignition switch do not respond to
Intelligent Key command. 1. Check Intelligent Key function and battery inspection.
DLK-102
2. Check Intelligent Key unit power supply and ground circuit. DLK-64
3. Check remote keyless entry receiver.DLK-99
4. Check BCM power supply and ground circuit.DLK-64
5. Replace Intelligent Key unit.DLK-102
Revision: March 2010 2008 QX56

SQUEAK AND RATTLE TROUBLE DIAGNOSESDLK-213
< SYMPTOM DIAGNOSIS > [WITH INTELLIGENT KEY SYSTEM]
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SQUEAK AND RATTLE TROUBLE DIAGNOSES
Work FlowINFOID:0000000001539076
CUSTOMER INTERVIEW
Interview the customer if possible, to determine the conditions that exist when the noise occurs.Use the Diag-
nostic Worksheet during the interv iew to document the facts and conditions when the noise occurs and any
customer's comments; refer to DLK-217, "
Diagnostic Worksheet". This information is necessary to duplicate
the conditions that exist when the noise occurs.
• The customer may not be able to provide a detailed descr iption or the location of the noise. Attempt to obtain
all the facts and conditions that exist when the noise occurs (or does not occur).
• If there is more than one noise in the vehicle, be sure to diagnose and repair the noise that the customer is
concerned about. This can be accomplished by test driving the vehicle with the customer.
• After identifying the type of noise, isolate the noise in terms of its characteristics. The noise characteristics
are provided so the customer, service adviser and technician are all speaking the same language when
defining the noise.
• Squeak —(Like tennis shoes on a clean floor)
Squeak characteristics include the light contact/fast movement/brought on by road conditions/hard surfaces
= higher pitch noise/softer surfaces = lower pitch noises/edge to surface = chirping
• Creak—(Like walking on an old wooden floor)
Creak characteristics include firm contact/slow mo vement/twisting with a rotational movement/pitch depen-
dent on materials/often brought on by activity.
• Rattle—(Like shaking a baby rattle)
Rattle characteristics include the fast repeated contac t/vibration or similar movement/loose parts/missing
clip or fastener/incorrect clearance.
• Knock —(Like a knock on a door)
Knock characteristics include hollow sounding/someti mes repeating/often brought on by driver action.
• Tick—(Like a clock second hand) Tick characteristics include gentle contacting of li ght materials/loose components/can be caused by driver
action or road conditions.
• Thump—(Heavy, muffled knock noise) Thump characteristics include softer k nock/dead sound often brought on by activity.
• Buzz—(Like a bumble bee)
Buzz characteristics include high frequency rattle/firm contact.
• Often the degree of acceptable noise level will vary depending upon the person. A noise that you may judge as acceptable may be very irritating to the customer.
• Weather conditions, especially humidity and temperature, may have a great effect on noise level.
DUPLICATE THE NOISE AND TEST DRIVE
If possible, drive the vehicle with the customer until the noise is duplicated. Note any additional information on
the Diagnostic Worksheet regarding the conditions or lo cation of the noise. This information can be used to
duplicate the same conditions when you confirm the repair.
SBT842
Revision: March 2010 2008 QX56

TRANSFER CONTROL UNITDLN-81
< ECU DIAGNOSIS > [ATX14B]
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ATP SWITCH [ON/OFF] Condition of ATP switch • Vehicle stopped
• Engine running
• A/T selector lever N posi-
tion
• 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 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: AUTO
ON
• 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 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 op-
erating.) ON
• Vehicle stopped
• Engine running
• 4WD shift switch: 2WD (Wait function is not operating.) OFF
N POSI SW AT [ON/
OFF] Input condition from A/T
transmission range
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
transmission range
switch • Vehicle stopped
• Engine running
• Brake pedal depressed A/T selector lever posi-
tion: R
ON
Except the above OFF
P POSI SW AT [ON/OFF] Input condition from A/T
transmission range
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 OPE R
SW [O

N/
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
Monitored item [Unit]
Content ConditionDisplay value
Revision: March 2010 2008 QX56

DLN-144
< DISASSEMBLY AND ASSEMBLY >[ATX14B]
TRANSFER ASSEMBLY
10. Remove the companion flange using suitable tool.
11. Remove the center case bolts, harness bracket and air breather.
12. Remove the filler plug and gasket.
13. Separate the center case from the front case. Then remove the
center case from the front case by prying it up using suitable
tool.
CAUTION:
Do not damage the mating surfaces.
14. Remove the shift rod components together with the 2-4 sleeve and L-H sleeve.
15. Remove the shift cross from the front case, using shift rod (A).
16. Remove the 2-4 sleeve and L-H sleeve from the 2-4 fork and L- H fork respectively.
WDIA0133E
SDIA2100E
SDIA2101E
AWDIA0015ZZ
SMT992C
Revision: March 2010 2008 QX56

EC-8
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis IntroductionINFOID:0000000001351337
INTRODUCTION
The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, or
other malfunctions with the engine.
It is much more difficult to diagnose an incident that occurs intermit-
tently rather than continuously. Most intermittent incidents are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-III (or GST) or a circuit tester connected should
be performed. Follow the Work Flow on "WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Di agnostic Worksheet like the example
on "Worksheet Sample" should be used.
Start your diagnosis by looking fo r conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.
WORK FLOW
MEF036D
SEF233G
SEF234G
Revision: March 2010 2008 QX56

INSPECTION AND ADJUSTMENTEC-13
< BASIC INSPECTION > [VK56DE]
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INSPECTION AND ADJUSTMENT
Basic InspectionINFOID:0000000001351329
1.INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leaks
- Air cleaner clogging
- Gasket
3. Confirm that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no load.
6. Make sure that no DTC is displayed with CONSULT-III or GST.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3.
3.CHECK TARGET IDLE SPEED
With CONSULT-III
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
SEF983U
SEF976U
SEF977U
Revision: March 2010 2008 QX56

EC-36
< FUNCTION DIAGNOSIS >[VK56DE]
COOLING FAN CONTROL
COOLING FAN CONTROL
DescriptionINFOID:0000000001351873
SYSTEM DESCRIPTION
Cooling Fan Control
*1: The ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to ECM through CAN communication line.
The ECM controls the cooling fan corresponding to the
vehicle speed, engine coolant temperature, refrigerant
pressure, and air conditioner ON signal. The c ontrol system has 2-step control [HI/OFF].
Cooling Fan Operation
SensorInput signal to ECMECM functionActuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
1
Cooling fan
controlIPDM E/R
(Cooling fan relay)
Battery
Battery voltage*
1
Wheel sensorVehicle speed*2
Engine coolant temperature sensor Engine coolant temperature
Air conditioner switch Air conditioner ON signal*
2
Refrigerant pressure sensorRefrigerant pressure
PBIB2060E
Revision: March 2010 2008 QX56

ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-43
< FUNCTION DIAGNOSIS > [VK56DE]
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Data which are stored in the ECM memory, along with the
1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are ca lled freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame dat a can only be displayed on the CONSULT-III screen, not on the GST. For
details, see EC-63, "
CONSULT-III Function (ENGINE)".
Only one set of freeze frame data (either 1st trip freez e frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the fr eeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st tr ip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame dat a (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in "HOW TO ERASE EMISSION-
RELATED DIAGNOSTIC INFORMATION".
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Service $01 of SAE J1979.
As part of an enhanced emissions test for Inspection & Ma intenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has comple ted self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
If, during the state emissions inspection, the SRT indicates “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT i ndicates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MIL is ON during the state emissi ons inspection, the vehicle is also returned to the customer untested even
though the SRT indicates “CMPLT” for all test items. T herefore, it is important to check SRT (“CMPLT”) and
DTC (No DTCs) before the inspection.
SRT Item
The table below shows required self-diagnostic items to set the SRT to “CMPLT”.
Priority Items
1 Freeze frame data Misfire — DTC: P0300 - P0308
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data
SRT item
(CONSULT-III indication) Performance
Priority* Required self-diagnostic items to set the SRT to “CMPLT”
Corresponding
DTC No.
CATALYST 2 Three way catalyst function P0420, P0430
Revision: March 2010 2008 QX56