2001 INFINITI QX4 INSTALLATION

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBBR0001The 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.
SBR686C
Precautions for Brake SystemNBBR0002IUse brake fluid ªDOT 3º.
INever reuse drained brake fluid.
IBe careful not to splash brake fluid on painted areas; it
may cause paint damage. If brake fluid is splashed on
painted areas, wash it away with water immediately.
ITo clean master cylinder parts, disc brake caliper parts or
wheel cylinder parts, use clean brake fluid.
INever use mineral oils such as gasoline or kerosene. They
will ruin rubber parts of hydraulic system.
IUse flare nut wrench when removing and installing brake
tubes.
IAlways torque brake lines when installing.
WARNING:
IClean brakes with a vacuum dust collector to minimize
risk of health hazard from powder caused by friction.
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PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
BR-3

SBR995
Bleeding Brake System=NBBR0009CAUTION:
ICarefully monitor brake fluid level at master cylinder dur-
ing bleeding operation.
IIf master cylinder is suspected to have air inside, bleed air
from master cylinder first. Refer to ªInstallationº, ªMAS-
TER CYLINDERº, BR-18.
IFill reservoir with new brake fluid ªDOT 3º. Make sure it is
full at all times while bleeding air out of system.
IPlace a container under master cylinder to avoid spillage
of brake fluid.
ITurn ignition switch OFF and disconnect ABS actuator
and electric unit connectors or battery ground cable.
IBleed air in the following order.
1. LSV air bleeder (4WD)
2. Left rear brake
3. Right rear brake
4. Left front brake
5. Right front brake
SBR419C
1. Connect a transparent vinyl tube to air bleeder valve.
2. Fully depress brake pedal several times.
3. With brake pedal depressed, open air bleeder valve to release
air.
4. Close air bleeder valve.
5. Release brake pedal slowly.
6. Repeat steps 2. through 5. until clear brake fluid comes out of
air bleeder valve.
7. Tighten air bleeder valve.
:7-9N´m(0.7 - 0.9 kg-m, 61 - 78 in-lb)
ON-VEHICLE SERVICE
Bleeding Brake System
BR-8

SBR992
RemovalNBBR0011CAUTION:
IBe careful not to splash brake fluid on painted areas; it
may cause paint damage. If brake fluid is splashed on
painted areas, wash it away with water immediately.
IAll hoses must be free from excessive bending, twisting
and pulling.
1. Connect vinyl tube to air bleeder valve.
2. Drain brake fluid from each air bleeder valve by depressing
brake pedal.
3. Remove flare nut connecting brake tube and hose, then with-
draw lock spring.
4. Cover openings to prevent entrance of dirt whenever discon-
necting brake line.
InspectionNBBR0012Check brake lines (tubes and hoses) for cracks, deterioration or
other damage. Replace any damaged parts.
SBR686C
InstallationNBBR0013CAUTION:
IRefill with new brake fluid ªDOT 3º.
INever reuse drained brake fluid.
1. Tighten all flare nuts and connecting bolts.
Flare nut:
: 15 - 17 N´m (1.5 - 1.8 kg-m, 11 - 13 ft-lb)
Connecting bolt:
: 17 - 19 N´m (1.7 - 2.0 kg-m, 12 - 14 ft-lb)
2. Refill until new brake fluid comes out of each air bleeder valve.
3. Bleed air. Refer to ªBleeding Brake Systemº, BR-8.
BRAKE HYDRAULIC LINE
Removal
BR-10

SBR822BA
InspectionNBBR0116
SBR823BA
SBR705AA
CAUTION:
ICarefully monitor brake fluid level at master cylinder.
IUse new brake fluid ªDOT 3º.
IBe careful not to splash brake fluid on painted areas; it
may cause paint damage. If brake fluid is splashed on
paint areas, wash it away with water immediately.
IDepress pedal slowly when raising front brake pressure.
ICheck rear brake pressure 2 seconds after front brake
pressure reaches specified value.
IDisconnect harness connectors from ABS actuator and
electric unit before checking.
1. Remove front LH tire.
2. Connect tool to air bleeders on front LH brake caliper and rear
LH or RH brake wheel cylinder.
3. Install front LH tire.
Before installing front LH tire, confirm the tool is not touching
the front LH wheel.
4. Bleed air from the tool.
5. Check fluid pressure by depressing brake pedal.
kPa (kg/cm2, psi)
Applied pressure (Front brake) D16,375 (65, 924)
Output pressure (Rear brake) D
23,432 - 3,825
(35 - 39, 498 - 555)
If output pressure is out of specifications, replace master cylinder
assembly (built-in type).
6. Bleed air after disconnecting the tool. Refer to ªBleeding Brake
Systemº, BR-8.
7. Install front LH tire.
Removal and Installation (Built-in type)NBBR0117Always replace together with master cylinder as an assembly.
IRefer to ªMASTER CYLINDERº, BR-16.
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PROPORTIONING VALVE (2WD)
Inspection
BR-11

InspectionNBBR0014CAUTION:
ICarefully monitor brake fluid level at master cylinder.
IUse new brake fluid ªDOT 3º.
IBe careful not to splash brake fluid on painted areas; it
may cause paint damage. If brake fluid is splashed on
paint areas, wash it away with water immediately.
IDepress pedal slowly when raising front brake pressure.
ICheck rear brake pressure 2 seconds after front brake
pressure reaches specified value.
IDisconnect harness connectors from ABS actuator and
electric unit before checking.
SBR212E
1. Park vehicle on a level surface with vehicle unloaded*.
* Fuel, radiator coolant and engine oil full. Spare tire, jack,
hand tools and mats in designated positions.
2. Press a lever to the stopper bolt, then check length ªBº as fol-
lows:
Length ªBº Reference (Length ªLº)
207.7 mm (8.18 in) 217.3 mm (8.56 in)
3. If length ªBº is not within specification, adjust sensor spring
length.
Removal and InstallationNBBR0015CAUTION:
IRefill with new brake fluid ªDOT 3º.
IBe careful not to splash brake fluid on painted areas; it
may cause paint damage. If brake fluid is splashed on
painted areas, wash it away with water immediately.
IDo not reuse Load Sensing Valve once it is disassembled.
IReplace damaged Load Sensing Valve as an assembly.
IWhen disassembling, apply multi-purpose grease to all
rubbing areas.
LOAD SENSING VALVE (4WD)
Inspection
BR-12

SBR379DC
1. Tighten all flare nuts and mounting bolts.
Flare nut:
: 15 - 17 N´m (1.5 - 1.8 kg-m, 11 - 13 ft-lb)
2. Refill until new brake fluid comes out of each air bleeder valve.
3. Bleed air. Refer to ªBleeding Brake Systemº, BR-8.
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LOAD SENSING VALVE (4WD)
Removal and Installation (Cont'd)
BR-13

Removal and InstallationNBBR0016
SBR520E
InspectionNBBR0017Check brake pedal for following items.
IBrake pedal bend
IClevis pin deformation
ICrack of any welded portion
ICrack or deformation of clevis pin stopper
SBR463CC
AdjustmentNBBR0018Check brake pedal free height from metal panel.
H: Free height
Refer to SDS (BR-83).
D: Depressed height
Refer to SDS (BR-83).
Under force of 490 N (50 kg, 110 lb) with engine run-
ning
C
1,C2: Clearance between pedal stopper and
threaded end of stop lamp switch and ASCD switch
0.3 - 1.0 mm (0.012 - 0.039 in)
A: Pedal free play
1-3mm(0.04 - 0.12 in)
If necessary, adjust brake pedal free height.
BRAKE PEDAL AND BRACKET
Removal and Installation
BR-14

ABR190
InstallationNBBR0023CAUTION:
IRefill with new brake fluid ªDOT 3º.
INever reuse drained brake fluid.
1. Place master cylinder onto brake booster and secure mount-
ing nuts lightly.
2. Torque mounting nuts.
: 12 - 15 N´m (1.2 - 1.5 kg-m,9-11ft-lb)
3. Fill up reservoir tank with new brake fluid.
4. Plug all ports on master cylinder with fingers to prevent air
suction while releasing brake pedal.
5. Have driver depress brake pedal slowly several times until no
air comes out of master cylinder.
6. Fit brake lines to master cylinder.
7. Tighten flare nuts.
: 15 - 17 N´m (1.5 - 1.8 kg-m, 11 - 13 ft-lb)
8. Bleed air. Refer to ªBleeding Brake Systemº, BR-8.
MASTER CYLINDER
Installation
BR-18