2001 INFINITI QX4 wheel

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBSC0001The 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 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.
Wiring Diagrams and Trouble DiagnosisNBSC0002When 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
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
SC-2

STEERING SYSTEM
SECTION
ST
CONTENTS
PRECAUTIONS...............................................................2
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............2
Precautions for Steering System .................................2
PREPARATION...............................................................3
Special Service Tools ..................................................3
Commercial Service Tools ...........................................5
NOISE, VIBRATION AND HARSHNESS (NVH)
TROUBLESHOOTING.....................................................6
NVH Troubleshooting Chart.........................................6
ON-VEHICLE SERVICE..................................................7
Checking Steering Wheel Play ....................................7
Checking Neutral Position on Steering Wheel ............7
PRE-CHECKING........................................................7
CHECKING...............................................................7
Front Wheel Turning Angle ..........................................7
Checking Gear Housing Movement ............................8
Adjusting Rack Retainer ..............................................8
Checking and Adjusting Drive Belts ............................8
Checking Fluid Level ...................................................8
Checking Fluid Leakage ..............................................8
Bleeding Hydraulic System..........................................9
Checking Steering Wheel Turning Force ....................9
Checking Hydraulic System.......................................10
STEERING WHEEL AND STEERING COLUMN......... 11
Components............................................................... 11
Removal and Installation ........................................... 11
STEERING WHEEL................................................. 11
STEERING COLUMN...............................................12
Disassembly and Assembly .......................................13
Inspection...................................................................14
TILT MECHANISM...................................................14
STEERING TRANSFER GEAR.....................................15
Removal .....................................................................15
Installation ..................................................................16
Inspection...................................................................16
POWER STEERING GEAR AND LINKAGE................17
Components...............................................................17
Removal and Installation ...........................................18
Disassembly...............................................................19
Inspection...................................................................20
BOOT.....................................................................20
RACK.....................................................................20
PINION ASSEMBLY.................................................20
GEAR HOUSING CYLINDER....................................20
TIE-ROD OUTER AND INNER SOCKETS..................21
Assembly ...................................................................21
Adjustment .................................................................24
POWER STEERING OIL PUMP....................................27
Components...............................................................27
Pre-disassembly Inspection .......................................27
Disassembly...............................................................28
Inspection...................................................................29
Assembly ...................................................................29
SERVICE DATA AND SPECIFICATIONS (SDS).........32
General Specifications ...............................................32
Steering Wheel ..........................................................32
Steering Column ........................................................32
Steering Transfer Gear ..............................................32
Steering Gear and Linkage .......................................33
Power Steering ..........................................................33
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
RS
BT
HA
SC
EL
IDX

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBST0044The 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 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 Steering SystemNBST0002IBefore disassembly, thoroughly clean the outside of the unit.
IDisassembly should be done in a clean work area. It is important to prevent the internal parts from
becoming contaminated by dirt or other foreign matter.
IPlace disassembled parts in order, on a parts rack, for easier and proper assembly.
IUse nylon cloths or paper towels to clean the parts; common shop rags can leave lint that might
interfere with their operation.
IBefore inspection or reassembly, carefully clean all parts with a general purpose, non-flammable
solvent.
IBefore assembly, apply a coat of recommended power steering fluid* to hydraulic parts. Vaseline
may be applied to O-rings and seals. Do not use any grease.
IReplace all gaskets, seals and O-rings. Avoid damaging O-rings, seals and gaskets during instal-
lation. Perform functional tests whenever designated.
*: Genuine Nissan PSF II or equivalent. Refer to MA-11, ªFluids and Lubricantsº.
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
ST-2

Special Service ToolsNBST0003The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
KV48100700
(J26364)
Torque adapter
NT169
Measuring pinion rotating torque
ST35300000
(Ð)
Drift
NT073
Installing power steering oil pump oil seal
a: 59 mm (2.32 in) dia.
b: 45 mm (1.77 in) dia.
ST27180001
(J25726-A)
Steering wheel puller
NT544
Removing steering wheel
ST29020001
(J24319-01)
Ball joint remover
NT694
Removing ball joint
a: 34 mm (1.34 in)
b: 6.5 mm (0.256 in)
c: 61.5 mm (2.421 in)
KV48103500
(J26357 and J26357-10)
Pressure gauge
NT547
Measuring oil pressure
KV48102500
(Ð)
Pressure gauge adapter
NT542
Measuring oil pressure
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
RS
BT
HA
SC
EL
IDX
PREPARATION
Special Service Tools
ST-3

Tool number
(Kent-Moore No.)
Tool nameDescription
ST3127S000
(See J25765-A)
1 GG91030000
(J25765-A)
Torque wrench
2 HT62940000
(Ð)
Socket adapter
3 HT62900000
(Ð)
Socket adapter
NT541
Measuring turning torque
KV48104400
(Ð)
Rack seal ring reformer
NT550
Reforming teflon ring
a: 50 mm (1.97 in) dia.
b: 36 mm (1.42 in) dia.
c: 100 mm (3.94 in)
KV48103400
(Ð)
Torque adapter
NT236
Measuring steering transfer gear rotating
torque
KV48104200
(Ð)
Rear cover wrench
NT540
Removing and installing gear housing end
cover
a: 4 mm (0.16 in) dia.
b: 5 mm (0.20 in)
c: 3 mm (0.12 in) dia.
d: 5 mm (0.20 in)
(J43995)
Steering lock nut wrench
NT838
Adjusting steering pinion rotating torque
(J43996)
Steering rack adjustment
wrench
NT839
Adjusting steering pinion rotating torque
(J-44372)
Spring gauge
LST024
Measuring steering wheel turning force
PREPARATION
Special Service Tools (Cont'd)
ST-4

NBST0043
NVH Troubleshooting ChartNBST0043S01Use the chart below to help you find the cause of the symptom. If necessary, repair or replace these parts.
Reference pageST-8
ST-9
ST-21
ST-21
ST-21
ST-8
ST-7
ST-9
MA-13
Ð
ST-13
ST-8
ST-13
ST-13
ST-17
PD-3
PD-3
AX-3
AX-3
SU-3
SU-3
SU-3
BR-6
Possible cause and
SUSPECTED PARTS
Fluid level
Air in hydraulic system
Tie-rod ball joint swinging force
Tie-rod ball joint rotating torque
Tie-rod ball joint end play
Steering gear fluid leakage
Steering wheel play
Steering gear rack sliding force
Drive belt looseness
Improper steering wheel
Improper installation or looseness or tilt lock lever
Mounting rubber deterioration
Steering column deformation or damage
Improper installation or looseness of steering column
Steering linkage looseness
PROPELLER SHAFT
DIFFERENTIAL
DRIVE SHAFT
AXLE
SUSPENSION
TIRES
ROAD WHEEL
BRAKES
Symp-
tomSTEERINGNoise´´´´´´´´´ ´´´´´´´´
Shake´´´ ´ ´´´´´´
Vibration´´´´´ ´ ´´´´
Shimmy´´´ ´ ´´´´´
Judder´ ´ ´´´´´
´: Applicable
NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting Chart
ST-6

SST489B
Checking Steering Wheel PlayNBST00051. With wheels in a straight-ahead position, check steering wheel
play.
Steering wheel play:
35 mm (1.38 in) or less
2. If it is not within specification, check the following for loose or
worn components.
Steering gear assembly
Steering column
Front suspension and axle
SST490BA
Checking Neutral Position on Steering WheelNBST0006PRE-CHECKINGNBST0006S01IMake sure that wheel alignment is correct.
Wheel alignment:
Refer to SU-13, ªWheel Alignmentº.
IVerify that the steering gear is centered before removing the
steering wheel.
CHECKINGNBST0006S021. Check that the steering wheel is in the neutral position when
driving straight ahead.
2. If it is not in the neutral position, remove the steering wheel and
reinstall it correctly.
3. If the neutral position is between two teeth, loosen tie-rod lock
nuts. Turn the tie-rods by the same amount in opposite direc-
tions on both left and right sides.
SMA127
Front Wheel Turning AngleNBST00071. Rotate steering wheel all the way right and left; measure turn-
ing angle.
Turning angle of full turns:
Refer to SU-13, ªWheel Alignmentº.
SST651C
2. If it is not within specification, check rack stroke.
Rack stroke ªSº:
Refer to SDS (ST-33).
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
RS
BT
HA
SC
EL
IDX
ON-VEHICLE SERVICE
Checking Steering Wheel Play
ST-7

SST601C
Checking Gear Housing MovementNBST00081. Check the movement of steering gear housing during station-
ary steering on a dry paved surface.
IApply a force of 49 N (5 kg, 11 lb) to steering wheel to check
the gear housing movement.
Turn off ignition key while checking.
Movement of gear housing:
±2mm(±0.08 in) or less
2. If movement exceeds the limit, replace mount insulator after
confirming proper installation of gear housing clamps.
SST602C
Adjusting Rack RetainerNBST0009IPerform this driving test on a flat road.
a) Check whether vehicle moves in a straight line when steering
wheel is released.
b) Check whether steering wheel returns to neutral position when
steering wheel is released from a slightly turned (approx. 20É)
position.
IIf any abnormality is found, correct it by resetting adjusting
screw.
Checking and Adjusting Drive BeltsNBST0010Refer to MA-13, ªChecking Drive Beltsº.
SST280BA
Checking Fluid LevelNBST0011Check fluid level.
Use the correct range of the dipstick depending on the fluid tem-
perature. Use the ªHOTº range at 50 to 80ÉC (122 to 176ÉF), or the
ªCOLDº range at 0 to 30ÉC (32 to 86ÉF).
CAUTION:
IDo not overfill.
IRecommended fluid is Genuine Nissan PSF II or equiva-
lent. Refer to MA-11, ªFluids and Lubricantsº.
SST458C
Checking Fluid LeakageNBST0012Check the lines for improper attachment and for leaks, cracks,
damage, loose connections, chafing and deterioration.
1. Run engine between idle speed and 1,000 rpm.
Make sure temperature of fluid in oil tank rises to 60 to 80ÉC
(140 to 176ÉF).
2. Turn steering wheel right-to-left several times.
3. Hold steering wheel at each ªlockº position for five seconds
and carefully check for fluid leakage.
ON-VEHICLE SERVICE
Checking Gear Housing Movement
ST-8