2001 INFINITI QX4 brake fluid

DATA MONITOR MODENBBR0097S05
MONITOR ITEM CONDITION SPECIFICATION
FR RH SENSOR
FR LH SENSOR
RR RH SENSOR
RR LH SENSORDrive vehicle.
(Each wheel is rotating.)Wheel speed signal
(Almost the same speed as speedometer.)
STOP LAMP SW Brake is depressed.Depress the pedal: ON
Release the pedal: OFF
G-SWITCHHVehicle is driven.
Vehicle is stopped.
Brake is applied.During sudden braking while driving on high  roads (asphalt
roads, etc.): OFF
While vehicle is stopped or during constant-speed driving: ON
FR RH IN SOL
FR RH OUT SOL
FR LH IN SOL
FR LH OUT SOL
RR IN SOL
RR OUT SOL1. Drive vehicle at speeds
over 30 km/h (19 MPH) for at
least 1 minute.
2. Engine is running.Operating conditions for each solenoid valve are indicated. ABS
is not operating: OFF
MOTOR RELAYABS is not operating: OFF
ABS is operating: ON
ACTUATOR RELAY
Ignition switch is ON or
engine is running.Ignition switch ON (Engine stops): OFF
Engine running: ON
WARNING LAMPABS warning lamp is turned on: ON
ABS warning lamp is turned off: OFF
BATTERY VOLT Power supply voltage for control unit
ABS OPER SIGABS is not operating: OFF
ABS is operating: ON
H: 4WD model only
ACTIVE TEST MODENBBR0097S06
TEST ITEM CONDITION JUDGEMENT
FR RH SOLENOID
FR LH SOLENOID
RR SOLENOID
Engine is running.Brake fluid pressure control operation
IN SOL OUT SOL
UP (Increase): OFF OFF
KEEP (Hold): ON OFF
DOWN (Decrease): ON ON
ABS MOTORABS actuator motor
ON: Motor runs (ABS motor relay ON)
OFF: Motor stops (ABS motor relay OFF)
ABS OPER SIGIgnition switch is ON or
engine is running.ON: Set ABS OPER SIG ªONº (ABS is operating.)
OFF: Set ABS OPER SIG ªOFFº (ABS is not operating.)
G SWITCHHIgnition switch is ON.G SWITCH (G SENSOR)
ON: Set G SWITCH MONITOR ªONº (G switch circuit is
closed.)
OFF: Set G SWITCH MONITOR ªOFFº (G switch circuit is
open.)
H: 4WD models only
NOTE:
Active test will automatically stop ten seconds after the test starts. (TEST IS STOPPED monitor shows ON.)
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONABS
CONSULT-II Inspection Procedure (Cont'd)
BR-48

SEF233G
SEF234G
How to Perform Trouble Diagnoses for Quick
and Accurate Repair
NBBR0098INTRODUCTIONNBBR0098S01The ABS system has an electronic control unit to control major
functions. The control unit accepts input signals from sensors and
instantly drives the actuators. It is essential that both kinds of sig-
nals are proper and stable. It is also important to check for conven-
tional problems: such as air leaks in booster lines, lack of brake
fluid, or other problems with the brake system.
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 faulty wiring. In this case,
careful checking of suspicious circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the problems, so a
road test should be performed.
Before undertaking actual checks, take a few minutes to talk with
a customer who approaches with an ABS complaint. The customer
is a very good source of information on such problems; especially
intermittent ones. By talking to the customer, find out what symp-
toms are present and under what conditions they occur. Start your
diagnosis by looking for ªconventionalº problems first. This is one
of the best ways to troubleshoot brake problems on an ABS con-
trolled vehicle.
Also check related Service bulletins for information.
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TROUBLE DIAGNOSIS Ð INTRODUCTIONABS
How to Perform Trouble Diagnoses for Quick and Accurate Repair
BR-49

Preliminary CheckNBBR0099
1 CHECK BRAKE FLUID
Check brake fluid for contamination.
Has brake fluid been contaminated?
Ye s©Replace. GO TO 2.
No©GO TO 2.
2 CHECK BRAKE FLUID LEVEL
Check brake fluid level in reservoir tank.
Low fluid level may indicate brake pad wear or leakage from brake line.
SBR451D
Is brake fluid filled between MAX and MIN lines on reservoir tank?
Ye s©GO TO 3.
No©Fill up brake fluid. GO TO 3.
3 CHECK BRAKE LINE
Check brake line for leakage.
SBR389C
Is leakage present at or around brake lines, tubes or hoses or are any of these parts cracked or damaged?
Ye s©Repair. GO TO 4.
No©GO TO 4.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONABS
Preliminary Check
BR-50

6 RECHECK BRAKE FLUID LEVEL
Check brake fluid level in reservoir tank again.
SBR451D
Is brake fluid filled between MAX and MIN lines on reservoir tank?
Ye s©GO TO 7.
No©Fill up brake fluid.
7 CHECK WARNING LAMP ACTIVATION
Check warning lamp activation.
SBR672E
Does warning lamp turn on when ignition switch is turned ON?
Ye s©GO TO 8.
No©Check fuse, warning lamp bulb and warning lamp circuit.
8 CHECK WARNING LAMP DEACTIVATION
Check warning lamp for deactivation after engine is started.
Does warning lamp turn off when engine is started?
Ye s©GO TO 9.
No©Go to Self-diagnosis (BR-41, 44).
9 DRIVE VEHICLE
Drive vehicle at speeds over 30 km/h (19 MPH) for at least one minute.
Does warning lamp remain off after vehicle has been driven at 30 km/h (19 MPH) for at least one minute?
Ye s©INSPECTION END
No©Go to Self-diagnosis (BR-41, 44).
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONABS
Preliminary Check (Cont'd)
BR-52

1. ABS Works FrequentlyNBBR0107
1 CHECK BRAKE FLUID PRESSURE
Check brake fluid pressure distribution.
Refer to ªInspectionº, ªLOAD SENSING VALVEº, BR-12.
Is brake fluid pressure distribution normal?
Ye s©GO TO 2.
No©Repair. Then perform Preliminary Check.
Refer to BR-50.
2 CHECK WHEEL SENSOR
1. Check wheel sensor connector for terminal damage or loose connections.
2. Perform wheel sensor mechanical check.
Refer to ª7. CHECK SENSOR ROTORº in ªDIAGNOSTIC PROCEDUREº, ªWheel Sensor or Rotorº, BR-56.
Is wheel sensor mechanism OK?
Ye s©GO TO 3.
No©Repair.
3 CHECK FRONT AXLE
Check front axles for excessive looseness. Refer to AX-4, ªFront Wheel Bearingº.
Is front axle installed properly?
Ye s©Go to ª3. CHECK WARNING LAMP INDICATIONº in ª2. Unexpected Pedal Actionº,
BR-70.
No©Repair.
2. Unexpected Pedal ActionNBBR0108
1 CHECK BRAKE PEDAL STROKE
Check brake pedal stroke.
SBR540A
Is brake pedal stroke excessively large?
Ye s©Perform Preliminary Check. Refer to BR-50.
No©GO TO 2.
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TROUBLE DIAGNOSES FOR SYMPTOMSABS
1. ABS Works Frequently
BR-69

ABS Actuator and Electric UnitNBBR0079S07
SBR468E
REMOVALNBBR0079S07011. Disconnect battery cable.
2. Drain brake fluid. Refer to ªChanging Brake Fluidº, BR-7.
3. Remove mounting bracket fixing bolts and nuts.
4. Disconnect connector, brake pipes and remove fixing nuts and
actuator ground cable.
INSTALLATIONNBBR0079S0702CAUTION:
After installation, refill brake fluid. Then bleed air. Refer to
ªBleeding Brake Systemº, BR-8.
1. Tighten actuator ground cable.
Place ground cable at a notch of mounting bracket.
2. Connect brake pipes temporarily.
3. Tighten fixing bolts and nuts.
4. Tighten brake pipes.
5. Connect connector and battery cable.
REMOVAL AND INSTALLATIONABS
ABS Actuator and Electric Unit
BR-82

General SpecificationsNBBR0118Unit: mm (in)
Applied model2WD 4WD
Front brakeBrake model AD31VC
Cylinder bore diameter´number of pistons 44.45 (1.7500)´2
Pad
Length´width´thickness132.0´52.5´11
(5.20´2.067´0.43)
Rotor outer diameter´thickness 300´28 (11.81´1.10)
Rear brakeBrake model LT30C
Cylinder bore diameter 22.23 (7/8)
Lining length´width´thickness296´50´6.1
(11.65´1.97´0.240)
Drum inner diameter 295.0 (11.61)
Master cylinder Bore diameter 25.40 (1)
Control valveValve modelProportioning valve
within master cylinderLinkage type load
sensing valve
Split point
kPa (kg/cm
2, psi)´reducing ratio2,942 (30, 427)´0.2 (Variable)´0.18
Brake boosterBooster model M235T
Diaphragm diameterPri: 252 (9.92)
Sec: 205 (8.07)
Recommended brake fluidDOT 3
Disc BrakeNBBR0119Unit: mm (in)
Brake modelAD31VC
Pad wear limit Minimum thickness 2.0 (0.079)
Rotor repair limit Minimum thickness 26.0 (1.024)
Drum BrakeNBBR0120Unit: mm (in)
Brake modelLT30C
Lining wear limit Minimum thickness 1.5 (0.059)
Drum repair limitMaximum inner diameter 296.5 (11.67)
Out-of-round limit 0.03 (0.0012)
Brake PedalNBBR0121Unit: mm (in)
TransmissionA/T
Free height ªHº*175 - 185
(6.89 - 7.28)
Depressed height ªDº*
[under force of 490 N (50 kg, 110 lb) with engine running]70 (2.76)
Clearance ªCº between pedal stopper and threaded end of stop lamp switch or ASCD switch 0.3 - 1.0 (0.012 - 0.039)
Pedal free playAt clevis 1.0 - 3.0 (0.039 - 0.118)
At pedal pad1 - 3 (0.04 - 0.12)
*: Measured from surface of metal panel to pedal pad
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SERVICE DATA AND SPECIFICATIONS (SDS)
General Specifications
BR-83

SEF452Y
Idle Air Volume LearningNBEC0642
SEF454Y
SEF455Y
DESCRIPTIONNBEC0642S01ªIdle Air Volume Learningº is an operation to learn the idle air vol-
ume that keeps each engine within the specific range. It must be
performed under any of the following conditions:
IEach time IACV-AAC valve, throttle body or ECM is replaced.
IIdle speed or ignition timing is out of specification.
PRE-CONDITIONINGNBEC0642S02Before performing ªIdle Air Volume Learningº, make sure that all of
the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are
missed for even a moment.
IBattery voltage: More than 12.9V (At idle)
IEngine coolant temperature: 70 - 99ÉC (158 - 210ÉF)
IPNP switch: ON
IElectric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime running light systems, if
the parking brake is applied before the engine is started the
headlamp will not illuminate.
ICooling fan motor: Not operating
ISteering wheel: Neutral (Straight-ahead position)
IVehicle speed: Stopped
ITransmission: Warmed-up
For A/T models with CONSULT-II, drive vehicle until ªFLUID
TEMP SEº in ªDATA MONITORº mode of ªA/Tº system indi-
cates less than 0.9V.
For A/T models without CONSULT-II, drive vehicle for 10 min-
utes.
OPERATION PROCEDURENBEC0642S03With CONSULT-IINBEC0642S03011. Turn ignition switch ªONº and wait at least 1 second.
2. Turn ignition switch ªOFFº and wait at least 10 seconds.
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic ªPRE-CONDITION-
INGº (previously mentioned) are in good order.
5. Turn ignition switch ªOFFº and wait at least 10 seconds.
6. Start the engine and let it idle for at least 30 seconds.
7. Select ªIDLE AIR VOL LEARNº in ªWORK SUPPORTº mode.
8. Touch ªSTARTº and wait 20 seconds.
9. Make sure that ªCMPLTº is displayed on CONSULT-II screen.
If ªINCMPº is displayed, ªIdle Air Volume Learningº will not be
carried out successfully. In this case, find the cause of the
problem by referring to the NOTE below.
10. Rev up the engine two or three times. Make sure that idle
speed and ignition timing are within specifications.
ITEM SPECIFICATION
Idle speed 750±50 rpm (in ªPº or ªNº position)
Ignition timing 15ɱ5É BTDC (in ªPº or ªNº position)
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BASIC SERVICE PROCEDURE
Idle Air Volume Learning
EC-57