2023 INFINITI QX80 brakes

WARNING
.Never rely solely on the hill start
assist system to prevent the vehicle
from moving backward on a hill.
Always drive carefully and atten-
tively. Depress the brake pedal when
the vehicle is stopped on a steep hill.
Be especially careful when stopped
on a hill on frozen or muddy roads.
Failure to prevent the vehicle from
rolling backwards may result in a loss
of control of the vehicle and possible
serious injury or death.
. The hill start assist system is not
designed to hold the vehicle at a
standstill on a hill. Depress the brake
pedal when the vehicle is stopped on
a steep hill. Failure to do so may
cause the vehicle to roll backwards
and may result in a collision or serious
personal injury.
. The hill start assist system may not
prevent the vehicle from rolling back-
wards on a hill under all load or road
conditions. Always be prepared to
depress the brake pedal to prevent
the vehicle from rolling backwards.
Failure to do so may result in a
collision or serious personal injury. The hill start assist system automatically
keeps the brakes applied to help prevent the
vehicle from rolling backwards in the time it
takes the driver to release the brake pedal
and apply the accelerator when the vehicle is
stopped on a hill.
The hill start assist system will operate
automatically under the following condi-
tions:
.
The transmission is shifted to a forward
or reverse gear.
. The vehicle is stopped completely on a hill
by applying the brake.
The maximum holding time is 2 seconds.
After 2 seconds the vehicle will begin to roll
back and the hill start assist system will stop
operating completely.
The hill start assist system will not operate
when the transmission is shifted to the N
(Neutral) or P (Park) position or on a flat and
level road.
When the Vehicle Dynamic Control (VDC)
warning light illuminates in the meter, the hill
start assist system will not operate. (See
“Warning lights, indicator lights and audible
reminders” (P.2-11).)
Starting and driving5-123
HILL START ASSIST SYSTEM

5-126Starting and driving
NOTE:
When the SNOW mode is activated, the
Lane Departure Prevention (LDP), Blind
Spot Intervention (BSI), Distance Control
Assist (DCA), and Intelligent Cruise Control
(ICC) systems will be turned off automati-
cally if the vehicle is equipped with them.
SSD0622
The sonar system sounds a tone to inform
the driver of obstacles near the bumper.
When the sonar system is turned on, the
sonar view will automatically appear in the
touch screen display when the camera is
activated.
WARNING
.The sonar system is a convenience
but it is not a substitute for proper
parking.
. The driver is always responsible for
safety during parking and other maneuvers. Always look around and
check that it is safe to do so before
parking.
. Read and understand the limitations
of the sonar system as contained in
this section. The colors of the sonar
indicator indicates different dis-
tances to the object.
. Inclement weather or ultrasonic
sources such as an automatic car
wash, a truck’s compressed-air
brakes or a pneumatic drill may affect
the function of the system; this may
include reduced performance or a
false activation.
FRONT AND REAR SONAR SYSTEM

WAF0777X
Example
The system indicators
will appear when
the vehicle moves closer to an object.
SONAR LIMITATIONS
WARNING
Listed below are the system limitations
for the sonar system. Failure to operate
the vehicle in accordance with these
system limitations could result in serious
injury or death.
. Read and understand the limitations
of the sonar system as contained in
this section. Inclement weather may affect the function of the sonar
system; this may include reduced
performance or a false activation.
. The sonar system is deactivated at
speeds above 6 MPH (10 km/h). It is
reactivated at lower speeds.
. Inclement weather or ultrasonic
sources such as an automatic car
wash, a truck’s compressed-air
brakes or a pneumatic drill may affect
the function of the sonar system; this
may include reduced performance or
a false activation.
. The sonar system is not designed to
prevent contact with small or moving
objects. Always move slowly. The
system will not detect small objects
below the bumper or on the ground.
. The sonar system may not detect the
following objects: fluffy objects such
as snow, cloth, cotton, glass-wool,
etc.; thin objects such as rope, wire
and chain, etc.; or wedge-shaped
objects; complex-shaped objects or
multiple objects in close.
. The sonar system may not detect
objects at speed above 3 MPH (5
km/h) and may not detect certain
angular or moving objects. .
The sonar system may not operate in
the following conditions:
— When rain, snow, ice, dirt, etc. adheres to the sonar sensor.
— When a loud sound is heard in the area around the vehicle.
— When the surface of the obstacle is diagonal to the front or rear of
the vehicle.
— When a sonar sensor or the area around the sensor is extremely hot
or cold.
. The sonar system may unintention-
ally operate in the following condi-
tions:
— When there is overgrown grass in the area around the vehicle.
— When there are bumps, protru- sions or manhole covers on the
road surface.
— When the vehicle drives through a draped flag or a curtain.
— When there is an accumulation of snow or ice behind the vehicle.
— When driving on a steep hill.
Starting and driving5-131

BRAKING PRECAUTIONS
The brake system has two separate hydrau-
lic circuits. If one circuit malfunctions, you
will still have braking ability at two wheels.
You may feel a small click and hear a sound
when the brake pedal is fully depressed
slowly. This is not a malfunction and in-
dicates that the brake assist mechanism is
operating properly.
Hydraulically-assisted brakes
The hydraulically-assisted brake system is
designed to use a hydraulic pump driven
electrically, to assist braking. If the engine
stops, you can stop the vehicle by depressing
the foot brake pedal. However, greater foot
pressure on the foot brake pedal will be
required to stop the vehicle. The stopping
distance will be longer.
Wet brakes
When the vehicle is washed or driven
through water, the brakes may get wet. As
a result, your braking distance will be longer
and the vehicle may pull to one side during
braking.
To dry brakes, drive the vehicle at a safe
speed while lightly tapping the brake pedal
to heat-up the brakes. Do this until the
brakes return to normal. Avoid driving the
vehicle at high speeds until the brakesfunction correctly.
PARKING BRAKE BREAK-IN
Break in the parking brake shoes whenever
the stopping effect of the parking brake is
weakened or whenever the parking brake
shoes and/or drums/rotors are replaced, in
order to assure the best braking perfor-
mance.
This procedure is described in the vehicle
service manual. It is recommended you visit
an INFINITI retailer for this service.
Using the brakes
Avoid resting your foot on the brake pedal
while driving. This will cause overheating of
the brakes, wearing out the brake and pads
faster and reduce gas mileage.
To help save the brakes and to prevent the
brakes from overheating, reduce speed and
downshift to a lower gear before going
down a slope or long grade. Overheated
brakes may reduce braking performance and
could result in loss of vehicle control.
WARNING
.
While driving on a slippery surface,
be careful when braking, accelerating
or downshifting. Abrupt braking or
accelerating could cause the wheels to skid and result in an accident.
. If the engine is not running or is
turned off while driving, the power
assist for the brakes will not work.
Braking will be harder.
Starting and driving5-133
BRAKE SYSTEM

5-134Starting and driving
BRAKE ASSIST
When the force applied to the brake pedal
exceeds a certain level, the Brake Assist is
activated generating greater braking force
than a conventional brake booster even with
light pedal force.
WARNING
The Brake Assist is only an aid to assist
braking operation and is not a collision
warning or avoidance device. It is the
driver’s responsibility to stay alert, drive
safely and be in control of the vehicle at
all times.
ANTI-LOCK BRAKING SYSTEM
(ABS)
WARNING
.The Anti-lock Braking System (ABS)
is a sophisticated device, but it
cannot prevent accidents resulting
from careless or dangerous driving
techniques. It can help maintain ve-
hicle control during braking on slip-
pery surfaces. Remember that
stopping distances on slippery sur- faces will be longer than on normal
surfaces even with ABS. Stopping
distances may also be longer on
rough, gravel or snow covered roads,
or if you are using tire chains. Always
maintain a safe distance from the
vehicle in front of you. Ultimately,
the driver is responsible for safety.
. Tire type and condition may also
affect braking effectiveness.
— When replacing tires, install the specified size of tires on all four
wheels.
— When installing a spare tire, make sure that it is the proper size and
type as specified on the Tire and
Loading Information label. See
“Tire and loading information la-
bel” (P.10-13).
— For detailed information, see “Wheels and tires” (P.8-27).
The Anti-lock Braking System (ABS) controls
the brakes so the wheels do not lock during
hard braking or when braking on slippery
surfaces. The system detects the rotation
speed at each wheel and varies the brake
fluid pressure to prevent each wheel from
locking and sliding. By preventing each
wheel from locking, the system helps the driver maintain steering control and helps to
minimize swerving and spinning on slippery
surfaces.
Using the system
Depress the brake pedal and hold it down.
Depress the brake pedal with firm steady
pressure, but do not pump the brakes. The
ABS will operate to prevent the wheels from
locking up. Steer the vehicle to avoid
obstacles.
WARNING
Do not pump the brake pedal. Doing so
may result in increased stopping dis-
tances.
Self-test feature
The ABS includes electronic sensors, electric
pumps, hydraulic solenoids and a computer.
The computer has a built-in diagnostic
feature that tests the system each time you
start the engine and move the vehicle at a
low speed in forward or reverse. When the
self-test occurs, you may hear a “clunk”
noise and/or feel a pulsation in the brake
pedal. This is normal and does not indicate a
malfunction. If the computer senses a mal-
function, it switches the ABS off and
BRAKE ASSIST

illuminates the ABS warning light on the
instrument panel. The brake system then
operates normally, but without anti-lock
assistance.
If the ABS warning light illuminates during
the self-test or while driving, have the
vehicle checked. It is recommended you visit
an INFINITI retailer for this service.
Normal operation
The ABS operates at speeds above 3 to 6
MPH (5 to 10 km/h). The speed varies
according to road conditions.
When the ABS senses that one or more
wheels are close to locking up, the actuator
rapidly applies and releases hydraulic pres-
sure. This action is similar to pumping the
brakes very quickly. You may feel a pulsation
in the brake pedal and hear a noise from
under the hood or feel a vibration from the
actuator when it is operating. This is normal
and indicates that the ABS is operating
properly. However, the pulsation may indi-
cate that road conditions are hazardous and
extra care is required while driving.The Vehicle Dynamic Control (VDC) system
uses various sensors to monitor driver inputs
and vehicle motion. Under certain driving
conditions, the VDC system helps to perform
the following functions.
.
Controls brake pressure to reduce wheel
slip on one slipping drive wheel so power
is transferred to a non slipping drive
wheel on the same axle.
. Controls brake pressure and engine out-
put to reduce drive wheel slip based on
vehicle speed (traction control function).
. Controls brake pressure at individual
wheels and engine output to help the
driver maintain control of the vehicle in
the following conditions:
— understeer (vehicle tends to not follow the steered path despite increased
steering input)
— oversteer (vehicle tends to spin due to certain road or driving conditions).
The VDC system can help the driver to
maintain control of the vehicle, but it cannot
prevent loss of vehicle control in all driving
situations.
When the VDC system operates, the VDC
warning light
in the instrument panel
flashes so note the following:
. The road may be slippery or the system
may determine some action is required to
help keep the vehicle on the steered path. .
You may feel a pulsation in the brake
pedal and hear a noise or vibration from
under the hood. This is normal and
indicates that the VDC system is working
properly.
. Adjust your speed and driving to the road
conditions.
If a malfunction occurs in the system, the
VDC warning light
illuminates in the
instrument panel. The VDC system automa-
tically turns off.
The VDC OFF switch is used to turn off the
VDC system. The VDC off indicator
illuminates to indicate the VDC system is off.
When the VDC switch is used to turn off the
system, the VDC system still operates to
prevent one drive wheel from slipping by
transferring power to a non slipping drive
wheel. The VDC warning light
flashes if
this occurs. All other VDC functions are off,
and the VDC warning light
will not flash.
The VDC system is automatically reset to on
when the ignition switch is placed in the off
position then back to the on position.
When the 4L position is selected with the
4WD shift switch, the VDC system is
disabled and the VDC off indicator light
illuminates (for 4WD models).
See “Vehicle Dynamic Control (VDC) warn-
ing light” (P.2-18) and “Vehicle Dynamic
Control (VDC) off indicator light” (P.2-18).
Starting and driving5-135
VEHICLE DYNAMIC CONTROL
(VDC) SYSTEM

8 Do-it-yourself
Maintenance precautions ............................................... 8-2
Engine compartment check locations ......................... 8-3VK56VD engine model .............................................. 8-3
Engine cooling system ..................................................... 8-4 Checking engine coolant level ................................. 8-5
Changing engine coolant .......................................... 8-5
Engine oil ........................................................................\
..... 8-6 Checking engine oil level ........................................... 8-6
Changing engine oil and filter .................................. 8-6
Automatic Transmission Fluid (ATF) .......................... 8-8
Power steering fluid ......................................................... 8-8
Brake fluid ........................................................................\
... 8-9 Brake fluid ..................................................................... 8-9
Window washer fluid ................................................... 8-10
Battery ........................................................................\
....... 8-11 Jump starting ............................................................. 8-12
Variable voltage control system ................................. 8-13
Drive belts ........................................................................\
. 8-13
Spark plugs ....................................................................... 8-14 Replacing spark plugs .............................................. 8-14
Air cleaner ........................................................................\
. 8-14 Windshield wiper blades .............................................. 8-15
Cleaning ..................................................................... 8-15
Replacing ................................................................... 8-16
Rear window wiper blades .......................................... 8-16
Brakes ........................................................................\
........ 8-17 Self-adjusting brakes ............................................. 8-17
Brake pad wear warning ....................................... 8-17
Brake booster ........................................................... 8-17
Fuses ........................................................................\
.......... 8-18 Engine compartment .............................................. 8-18
Passenger compartment ...................................... 8-20
Intelligent Key battery replacement ......................... 8-21
Lights ........................................................................\
......... 8-23
Headlights ................................................................ 8-24
Exterior and interior lights ................................... 8-24
Wheels and tires ............................................................. 8-27
Tire pressure ............................................................. 8-27
Tire labeling .............................................................. 8-31
Types of tires .......................................................... 8-34
Tire chains ................................................................. 8-35
Changing wheels and tires ................................... 8-35

If the brakes do not operate properly, have
the brakes checked. It is recommended that
you visit an INFINITI retailer for this service.
SELF-ADJUSTING BRAKES
Your vehicle is equipped with self-adjusting
brakes.
The disc-type brakes self-adjust every time
the brake pedal is applied.
WARNING
Have your brake system checked if the
brake pedal height does not return to
normal. It is recommended you visit an
INFINITI retailer for this service.
BRAKE PAD WEAR WARNING
The disc brake pads have audible wear
warnings. When a brake pad requires repla-
cement, it will make a high pitched scraping
sound when the vehicle is in motion. This
scraping sound will first occur only when the
brake pedal is depressed. After more wear of
the brake pad, the sound will always be
heard even if the brake pedal is not
depressed. Have the brakes checked as soon
as possible if the wear warning sound is
heard.
Under some driving or climate conditions,occasional brake squeak, squeal or other
noise may be heard. Occasional brake noise
during light to moderate stops is normal and
does not affect the function or performance
of the brake system.
Proper brake inspection intervals should be
followed.
For additional information, see the
maintenance schedules shown in the “9.
Maintenance and schedules” section.
BRAKE BOOSTER
Check the brake booster function as follows:
1. With the engine off, depress and release the foot brake pedal more than 20 times.
When the foot brake pedal movement
(distance of travel) remains the same
from one pedal application to the next,
continue on to the next step.
2. While depressing the foot brake pedal, start the engine.
3. With the foot brake pedal depressed, stop the engine. Keep the pedal de-
pressed for about 30 seconds.
4. Run the engine for 1 minute without depressing the foot brake pedal, then
turn it off. Depress the foot brake pedal
several times. The pedal travel distance
will decrease gradually with each de-
pression as the hydraulic pressure de-
creases. If the brakes do not operate properly, have
the brakes checked. It is recommended that
you visit an INFINITI retailer for repair.
Do-it-yourself8-17
BRAKES