2001 INFINITI QX4 engine

SBR002A
SBR365AA
On-vehicle ServiceNBBR0024OPERATING CHECKNBBR0024S011. Depress brake pedal several times with engine off. After
exhausting vacuum, make sure there is no change in pedal
stroke.
2. Depress brake pedal, then start engine. If pedal goes down
slightly, operation is normal.
AIRTIGHT CHECKNBBR0024S021. Start engine, and stop it after one or two minutes. Depress
brake pedal several times slowly. Booster is airtight if pedal
stroke is less each time.
2. Depress brake pedal while engine is running, and stop engine
with pedal depressed. The pedal stroke should not change
after holding pedal down for30 seconds.
SBR368DA
RemovalNBBR0025CAUTION:
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.
IBe careful not to deform or bend brake pipes, during
removal of booster.
SBR208E
InspectionNBBR0026OUTPUT ROD LENGTH CHECKNBBR0026S011. Apply vacuum of þ66.7 kPa (þ500 mmHg, þ19.69 inHg) to
brake booster with a hand vacuum pump.
2. Add preload of 19.6 N (2.0 kg, 4.4 lb) to output rod.
3. Check output rod length.
Specified length:
10.275 - 10.525 mm (0.4045 - 0.4144 in)
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BRAKE BOOSTER
On-vehicle Service
BR-19

SBR382D
Vacuum HoseNBBR0028
SBR225B
Removal and InstallationNBBR0029CAUTION:
When installing vacuum hoses, pay attention to the following
points.
IDo not apply any oil or lubricants to vacuum hose and
check valve.
IInsert vacuum tube into vacuum hose as shown.
SBR498A
IInstall check valve, paying attention to its direction.
InspectionNBBR0030HOSES AND CONNECTORSNBBR0030S01Check vacuum lines, connections and check valve for airtightness,
improper attachment chafing and deterioration.
SBR943A
CHECK VALVENBBR0030S02Check vacuum with a vacuum pump.
Connect to booster side Vacuum should exist.
Connect to engine side Vacuum should not exist.
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VACUUM PIPING
Vacuum Hose
BR-21

SBR042D
AdjustmentNBBR00471. Adjust clearance between shoe and drum as follows:
a. Release parking brake lever and loosen adjusting nut.
b. Depress brake pedal fully at least 10 times with engine run-
ning.
2. Pull control lever4-5notches. Then adjust control lever by
turning adjusting nut.
SBR073D
3. Pull control lever with specified amount of force. Check lever
stroke and ensure smooth operation.
Number of notches:6-8
4. Bend warning lamp switchplate to ensure:
IWarning lamp comes on when lever is lifted ªAº notches.
IWarning lamp goes out when lever is fully released.
Number of ªAº notches: 1 or less
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PARKING BRAKE CONTROL
Adjustment
BR-31

PurposeNBBR0087The Anti-Lock Brake System (ABS) consists of electronic and hydraulic components. It allows for control of
braking force so locking of the wheels can be avoided.
1) Improves proper tracking performance through steering wheel operation.
2) Eases obstacle avoidance through steering wheel operation.
3) Improves vehicle stability.
OperationNBBR0088IWhen the vehicle speed is less than 10 km/h (6 MPH) this system does not work.
IThe Anti-Lock Brake System (ABS) has a self-test function. The system turns on the ABS warning lamp
for 1 second each time the ignition switch is turned ªONº. After the engine is started, the ABS warning lamp
turns off. The system performs a test the first time the vehicle reaches 6 km/h (4 MPH). A mechanical noise
may be heard as the ABS performs this self-test. This is a normal part of the self-test feature. If a mal-
function is found during this check, the ABS warning lamp will stay on.
IWhile driving, a mechanical noise may be heard during ABS operation. This is a normal condition.
ABS Hydraulic CircuitNBBR0089
SBR859D
1. Inlet solenoid valve
2. Outlet solenoid valve
3. Reservoir4. Pump
5. Motor
6. Inlet valve7. Outlet valve
8. Bypass check valve
9. Damper
DESCRIPTIONABS
Purpose
BR-32

SBR665E
CONSULT-II Inspection Procedure=NBBR0097SELF-DIAGNOSIS PROCEDURENBBR0097S011. Turn ignition switch OFF.
2. Connect CONSULT-II to data link connector.
3. Start engine.
4. Drive vehicle over 30 km/h (19 MPH) for at least one minute.
PBR455D
5. Stop vehicle with engine running and touch ªSTARTº on CON-
SULT-II screen.
SBR670E
6. Touch ªABSº.
SBR636E
7. Touch ªSELF-DIAG RESULTSº.
IThe screen shows the detected malfunction and how many
times the ignition switch has been turned ON since the mal-
function.
8. Make the necessary repairs following the diagnostic proce-
dures.
PBR950C
9. After the malfunctions are repaired, erase the self-diagnostic
results stored in the control unit by touching ªERASEº.
10. Check warning lamp for deactivation after driving vehicle over
30 km/h (19 MPH) for at least one minute.
11. Test the ABS in a safe area to verify that it functions properly.
NOTE:
ªSELF-DIAG RESULTSº screen shows the detected malfunction
and how many times the ignition switch has been turned since the
malfunction.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONABS
CONSULT-II Inspection Procedure
BR-44

PBR455D
ACTIVE TEST PROCEDURE=NBBR0097S04IWhen conducting Active test, vehicle must be stationary.
IWhen ABS warning lamp stays on, never conduct Active test.
1. Turn ignition switch OFF.
2. Connect CONSULT-II to data link connector.
3. Start engine.
4. Touch ªSTARTº on CONSULT-II screen.
SBR670E
5. Touch ªABSº.
SBR636E
6. Touch ªACTIVE TESTº.
SBR671E
7. Select active test item by touching screen.
SBR639E
8. Touch ªSTARTº.
9. Carry out the active test by touching screen key.
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTIONABS
CONSULT-II Inspection Procedure (Cont'd)
BR-47

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

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