engine INFINITI QX4 2001 Factory Service Manual

Indicated items
(Screen terms for CONSULT, ªDATA
MONITORº mode)Display Conditions
Clutch pressure switch
(CL PRES SW)OFFIgnition switch in ªONº, and 4WD shift switch in ª2WDº.
(ªWaitº function is not operating.)
ONIgnition switch in ªONº, and 4WD shift switch in ªAUTOº
or ª4Hº and A/T selector lever in ªDº. (ªWaitº function is
not operating.)
Control torque
(COMP CL TORQ)0 kg-m
4WD shift switch
(ªWaitº function is not oper-
ating.)In ª2WDº position
39 - 1,079 N´m
(4 - 110 kg-m, 29 - 796 ft-lb)In ªAUTOº position
1,079 N´m
(110 kg-m, 796 ft-lb)In ª4Hº or ª4LOº position
4WD solenoid
(DUTY SOLENOID)4% In ª2WDº position
94 - 4% In ªAUTOº position
4% In ª4Hº or ª4LOº position
2-4WD shift solenoid valve
(2-4WD SOL)OFF
4WD shift switchIn ª2WDº position
ON (ªWaitº function is not oper-
ating.)
In ªAUTOº position
OFF (ªWaitº function is operat-
ing.)
ON (ªWaitº function is not oper-
ating.)
In ª4Hº position
OFF (ªWaitº function is operat-
ing.)
ON In ª4LOº position
Indicated items Display Conditions
Battery voltage Approx. 12V Key switch ªONº and engine at rest
Approx. 13 - 14V During idling
AUTO switch OFF 4WD shift switch in other than ªAUTOº position
ON 4WD shift switch in ªAUTOº position
4L switch OFF 4WD shift switch in other than ª4LOº position
ON 4WD shift switch in ª4LOº position
N position switch OFF A/T selector lever in other than ªNº position
ON A/T selector lever in ªNº position
R position swtich OFF A/T selector lever in other than ªRº position
ON A/T selector lever in ªRº position
P position switch OFF A/T selector lever in other than ªPº position
ON A/T selector lever in ªPº position
Throttle opening 0.0/8 - 8.0/8 Throttle fully closed (0.0/8) or throttle fully open (8.0/8)
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Trouble Diagnosis with CONSULT-II (Cont'd)
TF-37

Indicated items Display Conditions
4WD-mode2WD
4WD shift switchIn ª2WDº position
AUTO In ªAUTOº position
LOCK In ª4Hº position
4L In ª4LOº position
Front wheel speed 0 - 255 km/h (0 - 158 MPH) 0 km/h (vehicle at standstill)
Rear wheel speed 0 - 255 km/h (0 - 158 MPH) 0 km/h (vehicle at standstill)
Shift ACTR operating 1,
Shift activating monitor 1OFF During normal operation
ON During shifts from ª4Hº to ª4LOº position
Shift ACTR operating 2,
Shift activating monitor 2OFF During normal operation
ON During shifts from ª4LOº to ª4Hº position
4WD fail lamp OFF During normal operation
ONDuring 2-second period (after key switch turned to ªONº) or
when system is out of order
Shift ACTR position sensing
switch 1OFF 4WD shift switch is in a position other than ª4LOº.
ON 4WD shift switch in ª4LOº position
Shift ACTR position sensing
switch 2OFF 4WD shift switch in ª4LOº position
ON 4WD shift switch is in a position other than ª4LOº.
2WD indicator lamp OFF Engine at rest or system out of order
ON Except the above condition
AUTO indicator lamp
OFFEngine at rest during 2WD-mode operation or system out of
order
ON4WD shift switch in ª4LOº or ª4Hº position and A/T selector
lever in ªAUTOº position
LOCK indicator lamp
OFFEngine at rest and A/T selector lever in ªAUTOº position during
2WD-mode operation or system out of order
ON 4WD shift switch in ª4Hº or ª4LOº position
4L indicator lamp
OFFEngine at rest and A/T selector lever in ªAUTOº position during
2WD-mode operation or system out of order
ON 4WD shift switch in ª4LOº position
WORK SUPPORTNBTF0012S06PurposeNBTF0012S0601When there is no problem with transfer and 4WD system, follow-
ing symptoms in ªAUTOº mode may be claimed by a customer.
ITight corner braking symptom after accelerator (throttle) open-
ing (Note 1)
IVibration when accelerating on a low  road (snow-covered or
icy road) (Note 2)
It is possible to deal with these symptoms by changing
ªCLUTCH FORCE RELEASE LIMIT VALUEº. However, be
careful when changing the values because it may adversely
affect driving performance.
NOTE:
1) When the accelerator is slightly open (approx. 1/8) or fully
closed after being opened. The tight corner braking symptom
during idle creep driving with accelerator fully closed cannot be
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Trouble Diagnosis with CONSULT-II (Cont'd)
TF-38

IntroductionNBTF0013DESCRIPTIONNBTF0013S01When a malfunction (indicated by the 4WD warning lamp illumination) occurs, collect information first from the
customer about how the malfunction occurs. Then, proceed with the diagnosis presuming it is the cause. Also
inspect the electrical system, paying close attention to other possibilities such as fluid level and leaks.
All-mode 4WD transfer is controlled by transfer control unit and sensors.
If a malfunction occurs in the all-mode 4WD system, the 4WD warning lamp lights up to inform of the system
malfunction. There are two ways to identify the cause of the malfunction.
1) Performing the self-diagnosis. (The 4WD warning lamp will indicate what kind of malfunction has occurred
by flickering.)
2) Performing diagnosis using CONSULT-II.
DIAGNOSTIC WORKSHEETNBTF0013S02Information from CustomerNBTF0013S0201KEY POINTS
WHAT..... Vehicle model
WHEN..... Date, Frequencies
WHERE..... Road conditions
HOW..... Operating conditions, Symptoms
Information sheet from customer
Customer name MR/MS Model & Year VIN
Transfer model
ATX14AEngine Mileage
Incident Date Manuf. Date In Service Date
FrequencylContinuouslIntermittent ( times a day)
Symptomsl4WD shift indicator lamp does not turn on.
l4WD warning lamp does not turn on.
l4WD shift indicator lamp does not turn off.
lATP warning lamp does not turn on.
l4LO indicator lamp does not turn on.
l4WD shift indicator lamp does not indicate ª4Hº.
l4WD shift indicator lamp repeats flicking.
lTight corner braking symptom occurs.
l4WD system does not operate.
lOthers.
4WD warning lamplContinuously litlNot lit
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TROUBLE DIAGNOSIS Ð INTRODUCTION
Introduction
TF-41

Diagnostic WorksheetNBTF0013S0202
1.lListen to customer complaints.TF-44
2.lCheck transfer fluid.TF-44
lLeakage
lFluid condition
lFluid level
3.lRoad testingTF-44
l1. Check before engine is started.
l2. Check at idle.
l3. Cruise test
4.lPerform self-diagnosis NG items (with CONSULT-II and without CONSULT-II). TF-30, TF-27
5.lCheck component. Repair or replace the damaged parts. TF-111
6.lPerform final check. Perform road test (1 through 3). TF-44
TROUBLE DIAGNOSIS Ð INTRODUCTION
Introduction (Cont'd)
TF-42

Listen to Customer ComplaintsNBTF0015IEach customer feels differently about a problem. It is important
to fully understand the symptoms or conditions for a customer
complaint.
IListen to the customer about how and when the malfunction
occurs, and make good use of it when performing the road test.
Transfer Fluid CheckNBTF0016ICheck fluid for leaks and fluid level. Refer to MA-22, ªCheck-
ing All-mode 4WD Transfer Fluidº.
SMT089D
Road TestNBTF0017PREPARATION FOR ROAD TESTNBTF0017S01IThe purpose of the test is to determine overall performance of
transfer and analyze causes of problems.
IThe road test consists of the following three parts:
IWhen a malfunction is found in any part of transfer, perform the
road test to locate the malfunction area and repair the malfunc-
tion parts.
1. Check before engine is started
2. Check at idle
3. Cruise test
IPerform road test and place checks for NG items on the diag-
nostic worksheet. Refer to TF-42.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Listen to Customer Complaints
TF-44

1. CHECK BEFORE ENGINE IS STARTED=NBTF0017S02
1 CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface.
2. Turn ignition switch to ªOFFº position.
3. Move A/T selector lever to ªPº position.
4. Set 4WD shift switch to ª4Hº position.
SMT849D
5. Set 4WD shift switch to ª2WDº position.
6. Turn ignition switch to ªONº position. (Do not start engine.)
7. Does 4WD shift indicator lamp turn ON for approx. 1 second?
SMT958D
YesorNo
Ye s©GO TO 2.
No©Go to Symptom 1. Refer to TF-98.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Road Test (Cont'd)
TF-45

2. CHECK AT IDLE=NBTF0017S03
1 CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface.
2. Turn ignition switch to ªOFFº position.
3. Move A/T selector lever to ªPº or ªNº position.
4. Set 4WD shift switch to ª4Hº position.
5. Set 4WD shift switch to ª2WDº position.
6. Start engine.
7. Is 4WD shift indicator lamp turned OFF?
SMT958D
YesorNo
Ye s©Go to ªATP SWITCH, WAIT DETECTION SWITCH AND NEUTRAL-4LO SWITCHº. Refer
to TF-76.
No©GO TO 2.
2 CHECK 4WD WARNING LAMP
Is 4WD warning lamp turned OFF?
YesorNo
Ye s©GO TO 3.
No©Perform self-diagnosis. Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Road Test (Cont'd)
TF-47

2 CHECK INPUT SIGNAL
With CONSULT-II
1. Warm up engine to normal operating temperature.
2. Park vehicle on flat surface.
3. Move A/T selector lever to ªPº position.
4. Set 4WD shift switch to ª4Hº position.
5. Set 4WD shift switch to ªAUTOº position.
6. Start engine.
7. Drive for at least 30 seconds at a speed higher than 20 km/h (12 MPH).
(Drive vehicle until ªFLUID TEMP SEº exceeds 0.9V.)
8. Park vehicle on flat surface.
9. Move A/T selector lever to ªPº position.
10. Set 4WD shift switch to ª2WDº position.
11. Leave vehicle for at least 80 seconds with ªFLUID TEMP SEº at 0.9V or less.
SMT972D
12. Is 4WD warning lamp turned ON?
YesorNo
Ye s©Perform self-diagnosis. Refer to ªTrouble Diagnosis with CONSULT-IIº, TF-30.
No©GO TO 4.
3 CHECK INPUT SIGNAL
Without CONSULT-II
1. Warm up engine to normal operating temperature.
2. Park vehicle on flat surface.
3. Move A/T selector lever to ªPº position.
4. Set 4WD shift switch to ª4Hº position.
5. Set 4WD shift switch to ªAUTOº position.
6. Start engine.
7. Drive vehicle for at least 30 seconds at a speed higher than 20 km/h (12 MPH).
8. Park vehicle on flat surface.
9. Move A/T selector lever to ªPº position.
10. Set 4WD shift switch to ª2WDº position.
11. Is 4WD warning lamp turned ON?
YesorNo
Ye s©Perform self-diagnosis. Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27.
No©GO TO 4.
4 (1) CHECK TIGHT CORNER BRAKING SYMPTOM
1. Set 4WD shift switch to ªAUTOº position.
2. Drive vehicle at speed lower than 20 km/h (12 MPH) with steering wheel fully turned.
3. Does tight corner braking symptom occur?
YesorNo
Ye s©GO TO 5.
No©GO TO 6.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Road Test (Cont'd)
TF-52

SMT772D
TRANSFER CONTROL UNIT INSPECTION TABLENBTF0018S02(Data are reference values.)
Terminal
No.Item Condition Judgement standard
12-4WD shift solenoid
valve
&
4WD shift switch is set to ª2WDº
position.Less than 1V
4WD shift switch is set to any posi-
tion other than ª2WDº.Battery voltage
24WD shift indicator lamp
(2WD)
Lamp lights while system is operating
properly.Less than 1V
&
2WD indicator lamp does not come
on.Battery voltage
3 Ground Ð Ð
4Transfer shift relay
(High)While actuator is operating
(4H,4LO)Battery voltage
Actuator does not operate. Less than 1V
5 4WD warning lampLamp comes ON. (when engine is
stopped.)
(Fail-safe condition appears on
display, engine is stopped, actuator
position detection switch is
inoperative, oil temperature is too
high and/or tires of different size are
installed.)Less than 1V
Except above Battery voltage
6 Ground Ð Ð Ð
7 PNP switch (R position)
&
A/T selector lever is set to ªreverseº
position.Battery voltage
A/T selector lever is set to any posi-
tion other than ªreverseº.Less than 1V
8ÐÐÐÐ
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TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTION
Transfer Control Unit Terminals and Reference Value (Cont'd)
TF-55

4 CHECK INPUT SIGNAL
With CONSULT-II
1. Start engine.
2. Select ªECU INPUT SIGNALSº in Data Monitor.
3. Read out the value of ªVEHICLE SPEED SENSOR (FRONT)º while driving.
SMT773D
SMT974D
4. Check if the value changes according to accelerating and decelerating the vehicle.
OK or NG
OK©GO TO 6.
NG©GO TO 7.
VEHICLE SPEED SENSOR (FRONT REVOLUTION SENSOR)
Diagnostic Procedure (Cont'd)
TF-62