2001 INFINITI QX4 service

IThe threads in one or more of the converter bolt holes are damaged.
ITransmission failure did not display evidence of damaged or worn internal parts, steel particles or clutch
plate lining material in unit and inside the fluid filter.
IVehicle has been exposed to high mileage (only). The exception may be where the torque converter clutch
dampener plate lining has seen excess wear by vehicles operated in heavy and/or constant traffic, such
as taxi, delivery or police use.
ATF COOLER SERVICENBAT0004S02Replace ATF cooler if excessive foreign material is found in oil pan or clogging strainer.
Replace radiator lower tank (which includes ATF cooler) with a new one and flush cooler line using cleaning
solvent and compressed air. Refer to LC-19, ªREMOVAL AND INSTALLATIONº.
OBD-II SELF-DIAGNOSISNBAT0004S03IA/T self-diagnosis is performed by the TCM in combination with the ECM. The results can be read through
the blinking pattern of the O/D OFF indicator or the malfunction indicator lamp (MIL). Refer to the table on
AT-38 for the indicator used to display each self-diagnostic result.
IThe self-diagnostic results indicated by the MIL are automatically stored in both the ECM and TCM
memories.
Always perform the procedure ªHOW TO ERASE DTCº on AT-35 to complete the repair and avoid
unnecessary blinking of the MIL.
IThe following self-diagnostic items can be detected using ECM self-diagnostic results mode* only when
the O/D OFF indicator lamp does not indicate any malfunctions.
þ PNP switch
þ A/T 1st, 2nd, 3rd, or 4th gear function
þ A/T TCC S/V function (lock-up)
*: For details of OBD-II, refer to EC-59, ªIntroductionº.
ICertain systems and components, especially those related to OBD, may use the new style slide-
locking type harness connector. For description and how to disconnect, refer to EL-5, ªDescrip-
tionº.
Wiring Diagrams and Trouble DiagnosisNBAT0005When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº.
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit.
When you perform trouble diagnosis, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUP IN TROUBLE DIAGNOSISº.
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº.
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PRECAUTIONS
Service Notice or Precautions (Cont'd)
AT-9

Special Service ToolsNBAT0006The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
ST2505S001
(J34301-C)
Oil pressure gauge set
1 ST25051001
(Ð)
Oil pressure gauge
2 ST25052000
(Ð)
Hose
3 ST25053000
(Ð)
Joint pipe
4 ST25054000
(Ð)
Adapter
5 ST25055000
(Ð)
Adapter
NT097
Measuring line pressure
ST07870000
(J37068)
Transmission case stand
NT421
Disassembling and assembling A/T
a: 182 mm (7.17 in)
b: 282 mm (11.10 in)
c: 230 mm (9.06 in)
d: 100 mm (3.94 in)
KV31102100
(J37065)
Torque converter one-
way clutch check tool
NT098
Checking one-way clutch in torque converter
ST25850000
(J25721-A)
Sliding hammer
NT422
Removing oil pump assembly
a: 179 mm (7.05 in)
b: 70 mm (2.76 in)
c: 40 mm (1.57 in) dia.
d: M12 x 1.75P
KV31102400
(J34285 and J34285-87)
Clutch spring compres-
sor
NT423
Removing and installing clutch return springs
a: 320 mm (12.60 in)
b: 174 mm (6.85 in)
PREPARATION
Special Service Tools
AT-10

Tool number
(Kent-Moore No.)
Tool nameDescription
ST33200000
(J26082)
Drift
NT091
Installing oil pump housing oil seal Installing rear
oil seal
a: 60 mm (2.36 in) dia.
b: 44.5 mm (1.752 in) dia.
(J34291)
Shim setting gauge set
NT101
Selecting oil pump cover bearing race and oil
pump thrust washer
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PREPARATION
Special Service Tools (Cont'd)
AT-11

SAT964I
Malfunction Indicator Lamp (MIL)=NBAT0183The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON
without the engine running. This is a bulb check.
IIf the MIL does not light up, refer to EL-114, ªSchematicº.
(Or refer to EC-648, ªWiring Diagramº.)
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction. For detail, refer to
EC-59, ªIntroductionº.
CONSULT-IINBAT0184After performing ªSELF-DIAGNOSTIC PROCEDURE (WITH CON-
SULT-II)º (AT-37), place check marks for results on the ªDIAGNOS-
TIC WORKSHEETº, AT-55. Reference pages are provided follow-
ing the items.
NOTICE:
1) The CONSULT-II electrically displays shift timing and lock-up
timing (that is, operation timing of each solenoid).
Check for time difference between actual shift timing and the
CONSULT-II display. If the difference is noticeable, mechani-
cal parts (except solenoids, sensors, etc.) may be malfunction-
ing. Check mechanical parts using applicable diagnostic pro-
cedures.
2) Shift schedule (which implies gear position) displayed on
CONSULT-II and that indicated in Service Manual may differ
slightly. This occurs because of the following reasons:
IActual shift schedule has more or less tolerance or allowance,
IShift schedule indicated in Service Manual refers to the point
where shifts start, and
IGear position displayed on CONSULT-II indicates the point
where shifts are completed.
3) Shift solenoid valve ªAº or ªBº is displayed on CONSULT-II at
the start of shifting. Gear position is displayed upon completion
of shifting (which is computed by TCM).
4) Additional CONSULT-II information can be found in the Opera-
tion Manual supplied with the CONSULT-II unit.
SAT014K
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)NBAT0184S011. Turn on CONSULT-II and touch ªENGINEº for OBD-II detected
items or touch ªA/Tº for TCM self-diagnosis.
If A/T is not displayed, check TCM power supply and ground
circuit. Refer to AT-92. If result is NG, refer to EL-9, ªSche-
maticº.
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Malfunction Indicator Lamp (MIL)
AT-37

SAT631IB
IntroductionNBAT0019
SAT632I
SEF234G
The TCM receives a signal from the vehicle speed sensor, throttle
position sensor or PNP switch and provides shift control or lock-up
control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is
capable of diagnosing malfunctioning parts while the ECM can
store malfunctions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good
operating condition and be free of valve seizure, solenoid valve
malfunction, etc.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electric connections or improper wiring. In this
case, careful checking of suspected circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems. A road
test with CONSULT-II (or GST) or a circuit tester connected should
be performed. Follow the ªWork Flowº. Refer to AT-57.
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 problems, espe-
cially intermittent ones. Find out what symptoms are present and
under what conditions they occur. A ªDiagnostic Worksheetº like the
example (AT-55) should be used.
Start your diagnosis by looking for ªconventionalº problems first.
This will help troubleshoot driveability problems on an electronically
controlled engine vehicle.
Also check related Service bulletins.GI
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TROUBLE DIAGNOSIS Ð INTRODUCTION
Introduction
AT-53

DIAGNOSTIC WORKSHEET=NBAT0019S01Information From CustomerNBAT0019S0101KEY POINTS
WHAT..... Vehicle & A/T model
WHEN..... Date, Frequencies
WHERE..... Road conditions
HOW..... Operating conditions, Symptoms
Customer name MR/MS Model & Year VIN
Trans. model Engine Mileage
Incident Date Manuf. Date In Service Date
FrequencylContinuouslIntermittent ( times a day)
SymptomslVehicle does not move. (lAny positionlParticular position)
lNo up-shift (l1st,2ndl2nd,3rdl3rd,O/D)
lNo down-shift (lO/D,3rdl3rd,2ndl2nd,1st)
lLockup malfunction
lShift point too high or too low.
lShift shock or slip (lN,DlLockuplAny drive position)
lNoise or vibration
lNo kickdown
lNo pattern select
lOthers
()
O/D OFF indicator lamp Blinks for about 8 seconds.
lContinuously litlNot lit
Malfunction indicator lamp (MIL)lContinuously litlNot lit
TROUBLE DIAGNOSIS Ð INTRODUCTION
Introduction (Cont'd)
AT-54

6. Vehicle Does Not Creep Backward In ªRº
Position
=NBAT0078SYMPTOM:
Vehicle does not creep backward when selecting ªRº position.
1 CHECK A/T FLUID LEVEL
Check A/T fluid level again.
SAT638A
OK or NG
OK©GO TO 2.
NG©Refill ATF.
2 CHECK STALL TEST
Check stall revolution with selector lever in ª1º and ªRº positions.
Refer to AT-356.
SAT493G
OK or NG
OK©GO TO 3.
OK in ª1º position, NG in
ªRº position©1. Remove control valve assembly. Refer to ªON-VEHICLE SERVICEº, AT-273.
2. Check the following items:
IValves to control line pressure (Pressure regulator valve, pressure modifier valve, pilot
valve and pilot filter)
ILine pressure solenoid valve
3. Disassemble A/T.
4. Check the following items:
IOil pump assembly
ITorque converter
IReverse clutch assembly
IHigh clutch assembly
NG in both ª1º and ªRº
positions©GO TO 6.
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TROUBLE DIAGNOSES FOR SYMPTOMS
6. Vehicle Does Not Creep Backward In ªRº Position
AT-227

3 CHECK LINE PRESSURE
Check line pressure at idle with selector lever in ªRº position. Refer to ªLINE PRESSURE TESTº, AT-62.
SAT494G
OK or NG
OK©GO TO 4.
NG©1. Remove control valve assembly. Refer to ªON-VEHICLE SERVICEº, AT-273.
2. Check the following items:
IValves to control line pressure (Pressure regulator valve, pressure modifier valve, pilot
valve and pilot filter)
ILine pressure solenoid valve
3. Disassemble A/T.
4. Check the following items:
IOil pump assembly
4 CHECK A/T FLUID CONDITION
1. Remove oil pan.
2. Check A/T fluid condition.
SAT171B
OK or NG
OK©GO TO 5.
NG©GO TO 6.
5 CHECK SYMPTOM
Check again.
OK or NG
OK©INSPECTION END
NG©1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness con-
nector.
TROUBLE DIAGNOSES FOR SYMPTOMS
6. Vehicle Does Not Creep Backward In ªRº Position (Cont'd)
AT-228