2001 INFINITI QX4 wheel

Precautions for Supplemental Restraint System
(SRS) ªAIR BAGº and ªSEAT BELT
PRE-TENSIONERº
NBAT0001The supplemental Restraint System such as ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of
collision. The SRS system composition which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag module (located in the center of the steer-
ing wheel), front passenger air bag module (located on the instrument panel on passenger side), seat belt
pre-tensioners, a diagnosis sensor unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of front side air bag module (located in the outer side of front
seat), satellite sensor, diagnosis sensor unit (one of components of air bags for a frontal collision), wiring
harness, warning lamp (one of components of air bags for a frontal collision).
Information necessary to service the system safely is included in theRS sectionof this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, 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 INFINITI dealer.
IImproper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation tape either just
before the harness connectors or for the complete harness are related to the SRS.
Precautions for On Board Diagnostic (OBD)
System of A/T and Engine
NBAT0002The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
IBe sure to turn the ignition switch ªOFFº and disconnect the negative battery terminal before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc.
will cause the MIL to light up.
IBe sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to an open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
IBe sure to route and secure the harnesses properly after work. Interference of the harness with a
bracket, etc. may cause the MIL to light up due to a short circuit.
IBe sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to a malfunction of the EGR system or fuel injection system,
etc.
IBe sure to erase the unnecessary malfunction information (repairs completed) from the TCM and
ECM before returning the vehicle to the customer.
SEF289H
PrecautionsNBAT0003IBefore connecting or disconnecting the TCM harness
connector, turn ignition switch ªOFFº and disconnect
negative battery terminal. Failure to do so may damage
the TCM. Because battery voltage is applied to TCM even
if ignition switch is turned ªOFFº.
PRECAUTIONS
Precautions for Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
AT-6

IBefore assembly, apply a coat of recommended ATF to all
parts. Apply petroleum jelly to protect O-rings and seals, or
hold bearings and washers in place during assembly. Do not
use grease.
IExtreme care should be taken to avoid damage to O-rings,
seals and gaskets when assembling.
IReplace ATF cooler if excessive foreign material is found in oil
pan or clogging strainer. Refer to ªATF COOLER SERVICEº,
AT-9.
IAfter overhaul, refill the transmission with new ATF.
IWhen the A/T drain plug is removed, only some of the fluid is
drained. Old A/T fluid will remain in torque converter and ATF
cooling system.
Always follow the procedures when changing A/T fluid. Refer
to MA-21, ªChanging A/T Fluidº.
Service Notice or PrecautionsNBAT0004FAIL-SAFENBAT0004S01The TCM has an electronic Fail-Safe (limp home mode). This allows the vehicle to be driven even if a major
electrical input/output device circuit is damaged.
Under Fail-Safe, the vehicle always runs in third gear, even with a shift lever position of ª1º, ª2º or ªDº. The
customer may complain of sluggish or poor acceleration.
When the ignition key is turned ªONº following Fail-Safe operation, O/D OFF indicator lamp blinks for about
8 seconds. (For ªTCM SELF-DIAGNOSTIC PROCEDURE (No Tools)º, refer to AT-46.)
Fail-Safe may occur without electrical circuit damage if the vehicle is driven under extreme conditions (such
as excessive wheel spin followed by sudden braking). To recover normal shift pattern, turn the ignition key
ªOFFº for 5 seconds, then ªONº.
The blinking of the O/D OFF indicator lamp for about 8 seconds will appear only once and be cleared. The
customer may resume normal driving conditions.
Always follow the ªWORK FLOWº (Refer to AT-57).
The SELF-DIAGNOSIS results will be as follows:
The first SELF-DIAGNOSIS will indicate damage to the vehicle speed sensor or the revolution sensor.
During the next SELF-DIAGNOSIS, performed after checking the sensor, no damages will be indicated.
TORQUE CONVERTER SERVICENBAT0004S04The torque converter should be replaced under any of the following conditions:
IExternal leaks in the hub weld area.
IConverter hub is scored or damaged.
IConverter pilot is broken, damaged or fits poorly into crankshaft.
ISteel particles are found after flushing the cooler and cooler lines.
IPump is damaged or steel particles are found in the converter.
IVehicle has TCC shudder and/or no TCC apply. Replace only after all hydraulic and electrical diagnoses
have been made. (Converter clutch material may be glazed.)
IConverter is contaminated with engine coolant containing antifreeze.
IInternal failure of stator roller clutch.
IHeavy clutch debris due to overheating (blue converter).
ISteel particles or clutch lining material found in fluid filter or on magnet when no internal parts in unit are
worn or damaged Ð indicates that lining material came from converter.
The torque converter should not be replaced if:
IThe fluid has an odor, is discolored, and there is no evidence of metal or clutch facing particles.
PRECAUTIONS
Precautions (Cont'd)
AT-8

Torque Converter Clutch Control Valve OperationNBAT0180S0303
SAT048J
Lock-up Released
The OFF-duration of the torque converter clutch solenoid valve is
long, and pilot pressure is high. The pilot pressure pushes the end
face of the torque converter clutch control valve in combination with
spring force to move the valve to the left. As a result, converter
pressure is applied to chamber A (torque converter clutch piston
release side). Accordingly, the torque converter clutch piston
remains unlocked.
Lock-up Applied
When the OFF-duration of the torque converter clutch solenoid
valve is short, pilot pressure drains and becomes low. Accordingly,
the control valve moves to the right by the pilot pressure of the
other circuit and converter pressure. As a result, converter pres-
sure is applied to chamber B, keeping the torque converter clutch
piston applied.
Also smooth lock-up is provided by transient application and
release of the lock-up.
OVERRUN CLUTCH CONTROL (ENGINE BRAKE
CONTROL)
NBAT0180S04Forward one-way clutch is used to reduce shifting shocks in down-
shifting operations. This clutch transmits engine torque to the
wheels. However, drive force from the wheels is not transmitted to
the engine because the one-way clutch rotates idle. This means the
engine brake is not effective.
The overrun clutch operates when the engine brake is needed.
Overrun Clutch Operating ConditionsNBAT0180S0401
Gear position Throttle opening
ªDº position D
1,D2,D3gear position
Less than 3/16
ª2º position 2
1,22gear position
ª1º position 1
1,12gear position At any position
SAT014J
OVERALL SYSTEM
Control Mechanism (Cont'd)
AT-30

A/T Fluid CheckNBAT0021FLUID LEAKAGE CHECKNBAT0021S011. Clean area suspected of leaking. Ð for example, mating sur-
face of converter housing and transmission case.
2. Start engine, apply foot brake, place selector lever in ªDº posi-
tion and wait a few minutes.
3. Stop engine.
4. Check for fresh leakage.
SAT638A
FLUID CONDITION CHECKNBAT0021S02
Fluid color Suspected problem
Dark or black with burned odor Wear of frictional material
Milky pinkWater contamination Ð Road water
entering through filler tube or breather
Varnished fluid, light to dark brown
and tackyOxidation Ð Over or under filling, Ð
Overheating
FLUID LEVEL CHECKNBAT0021S03Refer to MA-21, ªChecking A/T Fluidº.
SAT647B
Stall TestNBAT0022STALL TEST PROCEDURENBAT0022S011. Check A/T fluid and engine oil levels. If necessary, add fluid
and oil.
2. Drive vehicle for approx. 10 minutes or until fluid and oil reach
operating temperature.
ATF operating temperature:
50 - 80ÉC (122 - 176ÉF)
SAT513G
3. Set parking brake and block wheels.
4. Install a tachometer where it can be seen by driver during test.
IIt is good practice to put a mark on point of specified
engine rpm on indicator.
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TROUBLE DIAGNOSIS Ð BASIC INSPECTION
A/T Fluid Check
AT-59

SAT209GA
Line Pressure TestNBAT0023ILocation of line pressure test ports.
IAlways replace line pressure plugs as they are self-seal-
ing bolts.
SAT647B
LINE PRESSURE TEST PROCEDURENBAT0023S011. Check A/T fluid and engine oil levels. If necessary, add fluid
and oil.
2. Drive vehicle for approx. 10 minutes or until fluid and oil reach
operating temperature.
ATF operating temperature:
50 - 80ÉC (122 - 176ÉF)
SAT518GB
SAT519GB
3. Install pressure gauge to corresponding line pressure port.
SAT513G
4. Set parking brake and block wheels.
IContinue to depress brake pedal fully while line pressure
test is being performed at stall speed.
TROUBLE DIAGNOSIS Ð BASIC INSPECTION
Line Pressure Test
AT-62

SAT801C
12. Support A/T and transfer assembly with a jack.
13. Remove rear engine mounting member from body and A/T
assembly. Tighten rear engine mounting member to the speci-
fied torque. Refer to EM-59, ªRear Engine Mountingº.
14. Remove bolts securing A/T assembly to engine.
ISecure torque converter to prevent it from dropping.
ISecure A/T assembly to a jack.
15. Lower A/T assembly with transfer.
SAT553J
SAT544J
Ð 2WD MODEL ÐNBAT0214S02CAUTION:
IDo not attach lifting cable to or place supporting fixture
under companion flange at rear of A/T (shown in the fig-
ure at left) when lifting/lowering A/T.
IBe sure to attach lifting cable to rear engine mounting or
dynamic damper location when lifting/lowering A/T.
1. Remove battery negative terminal.
2. Remove exhaust front and rear tubes.
3. Remove fluid charging pipe from A/T assembly.
4. Remove oil cooler pipe from A/T assembly.
5. Plug up openings such as the fluid charging pipe hole, etc.
6. Remove propeller shaft. Refer to PD-4, ªComponentsº.
7. Remove A/T control cable from A/T assembly.
8. Disconnect A/T and speedometer sensor harness connectors.
9. Remove starter motor. Refer to SC-18, ªRemoval and Installa-
tionº.
10. Remove gusset and rear plate cover securing engine to A/T
assembly.
11. Remove bolts securing torque converter to drive plate.
IRemove the bolts by turning crankshaft.
12. Support A/T assembly with a jack.
13. Remove rear engine mounting member from body and A/T
assembly. Tighten rear engine mounting member to the speci-
fied torque. Refer to EM-59, ªRear Engine Mountingº.
14. Remove bolts securing A/T assembly to engine.
15. Pull A/T assembly backwards.
ISecure torque converter to prevent it from dropping.
ISecure A/T assembly to a jack.
16. Lower A/T assembly.
SAT977H
InstallationNBAT0107IDrive plate runout
Maximum allowable runout:
Refer to EM-70, ªFLYWHEEL/DRIVE PLATE RUNOUTº.
If this runout is out of specification, replace drive plate with ring
gear.
REMOVAL AND INSTALLATION
Removal (Cont'd)
AT-278

FRONT & REAR AXLE
SECTION
AX
CONTENTS
FRONT AXLE..................................................................2
Precautions ..................................................................2
PRECAUTIONS.........................................................2
Preparation ..................................................................2
SPECIAL SERVICE TOOLS........................................2
COMMERCIAL SERVICE TOOLS................................2
Noise, Vibration and Harshness (NVH)
Troubleshooting ...........................................................3
NVH TROUBLESHOOTING CHART............................3
On-vehicle Service.......................................................3
FRONT AXLE PARTS................................................3
FRONT WHEEL BEARING.........................................4
DRIVE SHAFT...........................................................5
Wheel Hub and Rotor Disc..........................................6
COMPONENTS.........................................................6
REMOVAL.................................................................6
INSTALLATION..........................................................7
DISASSEMBLY..........................................................8
INSPECTION.............................................................8
ASSEMBLY...............................................................8
Knuckle Spindle ...........................................................9
REMOVAL.................................................................9
INSPECTION...........................................................10
INSTALLATION........................................................10
Drive Shaft .................................................................10
COMPONENTS.......................................................10
REMOVAL............................................................... 11
DISASSEMBLY........................................................ 11
INSPECTION...........................................................12
ASSEMBLY.............................................................13
INSTALLATION........................................................14
Service Data and Specifications (SDS).....................15
WHEEL BEARING (FRONT).....................................15
DRIVE SHAFT.........................................................16
REAR AXLE...................................................................17
Precautions ................................................................17
PRECAUTIONS.......................................................17
Preparation ................................................................17
SPECIAL SERVICE TOOLS......................................17
COMMERCIAL SERVICE TOOLS..............................18
Noise, Vibration and Harshness (NVH)
Troubleshooting .........................................................18
On-vehicle Service.....................................................18
REAR AXLE PARTS.................................................18
REAR WHEEL BEARING.........................................18
Components...............................................................19
Removal .....................................................................19
Inspection...................................................................21
AXLE SHAFT...........................................................21
BEARING CAGE......................................................21
REAR AXLE HOUSING............................................21
Installation ..................................................................21
Service Data and Specifications (SDS).....................22
WHEEL BEARING (REAR).......................................22
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SBR686C
Precautions
PRECAUTIONSNBAX0001IWhen installing rubber parts, final tightening must be car-
ried out under unladen condition* with tires on ground.
*Fuel, radiator coolant and engine oil full. Spare tire, jack,
hand tools and mats in designated positions.
IUse flare nut wrench when removing and installing brake
tubes.
IAfter installing removed suspension parts, check wheel
alignment and adjust if necessary.
IAlways torque brake lines when installing.
Preparation
SPECIAL SERVICE TOOLSNBAX0002The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
ST29020001
(J24319-01)
Ball joint remover
NT694
Removing tie-rod outer end and lower ball
joint
a: 34 mm (1.34 in)
b: 6.5 mm (0.256 in)
c: 61.5 mm (2.421 in)
KV401021S0
(Ð)
Bearing race drift
NT153
Installing wheel bearing outer race
KV40105400
(J36001)
Wheel bearing lock nut
wrench
NT154
Removing and installing wheel bearing lock
nut
COMMERCIAL SERVICE TOOLSNBAX0003
Tool name Description
1 Flare nut crowfoot
2 Torque wrench
NT360
Removing and installing each brake piping
a: 10 mm (0.39 in)
Hub cap drift
NT115
Installing hub cap
a: 57 mm (2.24 in) dia.
b: 46 mm (1.81 in) dia.
FRONT AXLE
Precautions
AX-2