2001 INFINITI QX4 warning

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

SAT132K
Throttle Position SwitchNBAT0204S0403Closed Throttle Position Switch (Idle Position)
ICheck continuity between terminals 5 and 6.
[Refer to ªPreparationº, ªTCM SELF-DIAGNOSTIC PROCE-
DURE (No Tools)º, AT-46.]
Accelerator pedal condition Continuity
Released Yes
Depressed No
ITo adjust closed throttle position switch, refer to EC-431, ªSystem
Descriptionº.
SAT137K
Wide Open Throttle Position Switch
ICheck continuity between terminals 4 and 5.
Accelerator pedal condition Continuity
Released No
Depressed Yes
SAT251JA
A/T Fluid Temperature SwitchNBAT0204S04041. Make sure the A/T fluid warning lamp lights when the key is
inserted and turned to ªONº.
2. Make sure the A/T fluid warning lamp goes off when turning the
ignition switch to ªONº.
3. Check resistance between terminal 10 and ground while
changing temperature as shown at left.
Temperature ÉC (ÉF) Resistance
140 (284) or more Yes
140 (284) or less No
TROUBLE DIAGNOSES FOR SYMPTOMS
21. TCM Self-diagnosis Does Not Activate (PNP, Overdrive Control and Throttle Position Switches Circuit Checks) (Cont'd)
AT-264

ABS
DESCRIPTION...............................................................32
Purpose......................................................................32
Operation ...................................................................32
ABS Hydraulic Circuit ................................................32
System Components .................................................33
System Description ....................................................33
SENSOR.................................................................33
CONTROL UNIT (BUILT-IN ABS ACTUATOR AND
ELECTRIC UNIT)
.....................................................33
ABS ACTUATOR AND ELECTRIC UNIT....................33
G SENSOR (4WD MODELS ONLY)..........................34
Component Parts and Harness Connector
Location .....................................................................35
Schematic ..................................................................36
Wiring Diagram - ABS - .............................................37
ON BOARD DIAGNOSTIC SYSTEM
DESCRIPTION...............................................................41
Self-diagnosis ............................................................41
FUNCTION..............................................................41
SELF-DIAGNOSIS PROCEDURE..............................41
HOW TO READ SELF-DIAGNOSTIC RESULTS
(MALFUNCTION CODES)
........................................42
HOW TO ERASE SELF-DIAGNOSTIC RESULTS
(MALFUNCTION CODES)
........................................42
CONSULT-II ...............................................................43
CONSULT-II APPLICATION TO ABS..........................43
ECU (ABS CONTROL UNIT) PART NUMBER
MODE
.....................................................................43
CONSULT-II Inspection Procedure............................44
SELF-DIAGNOSIS PROCEDURE..............................44
SELF-DIAGNOSTIC RESULTS MODE.......................45
DATA MONITOR PROCEDURE................................46
ACTIVE TEST PROCEDURE....................................47
DATA MONITOR MODE...........................................48
ACTIVE TEST MODE...............................................48
TROUBLE DIAGNOSIS - INTRODUCTION..................49
How to Perform Trouble Diagnoses for Quick
and Accurate Repair ..................................................49
INTRODUCTION......................................................49
TROUBLE DIAGNOSIS - BASIC INSPECTION...........50
Preliminary Check......................................................50
Ground Circuit Check ................................................53
ABS ACTUATOR AND ELECTRIC UNIT GROUND.....53
TROUBLE DIAGNOSIS - GENERAL
DESCRIPTION...............................................................54
Malfunction Code/Symptom Chart.............................54
TROUBLE DIAGNOSES FOR SELF-DIAGNOSTIC
ITEMS.............................................................................56Wheel Sensor or Rotor ..............................................56
DIAGNOSTIC PROCEDURE.....................................56
ABS Actuator Solenoid Valve or Solenoid Valve
Relay ..........................................................................59
DIAGNOSTIC PROCEDURE.....................................59
Motor Relay or Motor.................................................61
DIAGNOSTIC PROCEDURE.....................................61
Low Voltage ...............................................................63
DIAGNOSTIC PROCEDURE.....................................63
G Sensor and Circuit .................................................65
DIAGNOSTIC PROCEDURE.....................................65
ELECTRICAL COMPONENT INSPECTION................67
Control Unit ................................................................68
DIAGNOSTIC PROCEDURE.....................................68
TROUBLE DIAGNOSES FOR SYMPTOMS.................69
1. ABS Works Frequently ..........................................69
2. Unexpected Pedal Action ......................................69
3. Long Stopping Distance ........................................70
4. ABS Does Not Work ..............................................71
5. Pedal Vibration and Noise.....................................71
6. Warning Lamp Does Not Come On When
Ignition Switch Is Turned On .....................................72
7. Warning Lamp Stays On When Ignition Switch
Is Turned On ..............................................................74
8. Vehicle Vibrates Excessively When ABS Is
Operating ...................................................................77
REMOVAL AND INSTALLATION.................................80
Front Wheel Sensor...................................................80
Rear Wheel Sensor ...................................................80
Front Sensor Rotor ....................................................81
REMOVAL...............................................................81
INSTALLATION........................................................81
Rear Sensor Rotor.....................................................81
REMOVAL...............................................................81
INSTALLATION........................................................81
G Sensor....................................................................81
ABS Actuator and Electric Unit..................................82
REMOVAL...............................................................82
INSTALLATION........................................................82
SERVICE DATA AND SPECIFICATIONS (SDS).........83
General Specifications ...............................................83
Disc Brake .................................................................83
Drum Brake................................................................83
Brake Pedal ...............................................................83
Parking Brake Control ...............................................84
CONTENTS(Cont'd)
BR-2

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

SBR451D
Checking Brake Fluid LevelNBBR0006ICheck fluid level in reservoir tank. It should be between Max
and Min lines on reservoir tank.
IIf fluid level is extremely low, check brake system.
IIf the brake warning lamp comes on, check brake fluid level
switch and parking brake switch.
SBR389C
Checking Brake LineNBBR0007CAUTION:
If leakage occurs around joints, retighten or, if necessary,
replace damaged parts.
1. Check brake lines (tubes and hoses) for cracks, deterioration
or other damage. Replace any damaged parts.
2. Check for oil leakage by fully depressing brake pedal while
engine is running.
SBR419C
Changing Brake FluidNBBR0008CAUTION:
IRefill with new brake fluid ªDOT 3º.
IAlways keep fluid level higher than minimum line on res-
ervoir tank.
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.
1. Clean inside of reservoir tank, and refill with new brake fluid.
2. Connect a vinyl tube to each air bleeder valve.
3. Drain brake fluid from each air bleeder valve by depressing
brake pedal.
4. Refill until brake fluid comes out of each air bleeder valve.
Use same procedure as in bleeding hydraulic system to refill
brake fluid.
Refer to ªBleeding Brake Systemº, BR-8.
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ON-VEHICLE SERVICE
Checking Brake Fluid Level
BR-7

ComponentsNBBR0031
SBR385DC
1. Main pin
2. Pin boot
3. Torque member fixing bolt
4. Torque member
5. Shim cover
6. Inner shim7. Inner pad
8. Pad retainer
9. Outer pad
10. Outer shim
11. Connecting bolt
12. Copper washer13. Main pin bolt
14. Bleed valve
15. Cylinder body
16. Piston seal
17. Piston
18. Piston boot
Pad ReplacementNBBR0032WARNING:
Clean brakes with a vacuum dust collector to minimize the
hazard of airborne particles or other materials.
CAUTION:
IWhen cylinder body is open, do not depress brake pedal,
or piston will pop out.
IBe careful not to damage piston boot or get oil on rotor.
Always replace shims when replacing pads.
IIf shims are rusted or show peeling of the rubber coat,
replace them with new shims.
IIt is not necessary to remove connecting bolt except for
disassembly or replacement of caliper assembly. In this
case, suspend cylinder body with wire so as not to stretch
brake hose.
ICarefully monitor brake fluid level because brake fluid will
return to reservoir when pushing back piston.
FRONT DISC BRAKE
Components
BR-22

SBR383D
1. Remove master cylinder reservoir cap.
2. Remove lower pin bolt.
SBR384D
3. Open cylinder body upward. Then remove pad retainers, and
inner and outer shims.
Standard pad thickness:
11.0 mm (0.433 in)
Pad wear limit:
2.0 mm (0.079 in)
Carefully monitor brake fluid level because brake fluid will
return to reservoir when pushing back piston.
RemovalNBBR0033WARNING:
Clean brake pads with a vacuum dust collector to minimize the
hazard of airborne particles or other materials.
CAUTION:
Suspend caliper assembly with wire so as not to stretch brake
hose.
SBR386D
Remove torque member fixing bolts and connecting bolt.
It is not necessary to remove connecting bolt except for dis-
assembly or replacement of caliper assembly. In this case,
suspend caliper assembly with wire so as not to stretch brake
hose.
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FRONT DISC BRAKE
Pad Replacement (Cont'd)
BR-23

SBR085A
DisassemblyNBBR0034WARNING:
Do not place your fingers in front of piston.
CAUTION:
Do not scratch or score cylinder wall.
1. Push out piston with dust seal with compressed air.
2. Remove piston seal with a suitable tool.
InspectionNBBR0035CALIPERNBBR0035S01Cylinder BodyNBBR0035S0101ICheck inside surface of cylinder for score, rust, wear, damage
or presence of foreign objects. If any of the above conditions
are observed, replace cylinder body.
IMinor damage from rust or foreign objects may be eliminated
by polishing surface with a fine emery paper. Replace cylinder
body if necessary.
CAUTION:
Use brake fluid to clean. Never use mineral oil.
PistonNBBR0035S0102Check piston for score, rust, wear, damage or presence of foreign
objects. Replace if any of the above conditions are observed.
CAUTION:
Piston sliding surface is plated. Do not polish with emery
paper even if rust or foreign objects are stuck to sliding sur-
face.
Slide Pin, Pin Bolt and Pin BootNBBR0035S0103Check for wear, cracks, rust or other damage. Replace if any of the
above conditions are observed.
SBR019B
ROTORNBBR0035S02RunoutNBBR0035S02011. Secure rotor to wheel hub with at least two nuts (M12´1.25).
2. Check runout using a dial indicator.
Make sure that wheel bearing axial end play is within the
specifications before measuring. Refer to AX-4, ªFront Wheel
Bearingº.
Maximum runout:
0.1 mm (0.004 in)
3. If the runout is out of specification, find minimum runout posi-
tion as follows:
a. Remove nuts and rotor from wheel hub.
b. Shift the rotor one hole and secure rotor to wheel hub with
nuts.
c. Measure runout.
d. Repeat steps a. to c. so that minimum runout position can be
found.
4. If the runout is still out of specification, turn rotor with on-car
brake lathe (ªMAD, DL-8700º, ªAMMCO 700 and 705º or
equivalent).
FRONT DISC BRAKE
Disassembly
BR-24