brakes INFINITI QX80 2021 Owner's Guide

5-86Starting and driving
DCA SYSTEM OPERATION
WARNING
Failure to follow the warnings and
instructions for proper use of the DCA
system could result in serious personal
injury or death.
.When the vehicle ahead detection
indicator is not illuminated, system
will not control the vehicle or warn
the driver.
. Never place your foot under the
brake pedal. Your foot may be caught
when the system controls the brake.
. Depending on the position of the
accelerator pedal, the system may
not be able to assist the driver to
release the accelerator pedal appro-
priately.
The DCA system brakes and moves the
accelerator pedal upward according to the
distance from and the relative speed of the
vehicle ahead to help assist the driver in
maintaining a following distance. The sys-
tem will decelerate as necessary and if the
vehicle ahead comes to a stop, the vehicle
decelerates to a standstill. However, the
DCA system can only apply up to approxi- mately 40% of the vehicle’s total braking
power. If a vehicle moves into the traveling
lane ahead or if a vehicle traveling ahead
rapidly decelerates, the distance between
vehicles may become closer because the
DCA system cannot decelerate the vehicle
quickly enough. If this occurs, the DCA
system will sound a warning chime and blink
the system display to notify the driver to
take necessary action.
See “Approach warning” (P.5-88).

WAF0348X
System set display without a vehicle
ahead
System set display with a vehicle ahead
System set display with a vehicle ahead
(brake operation is necessary)
The DCA system helps assist the driver to
keep a following distance to the vehicle
ahead by braking and moving the accelera-
tor pedal upward in the normal driving
condition.
When a vehicle ahead is detected:
The vehicle ahead detection indicator (green)
comes on. When the vehicle approaches a vehicle
ahead:
.
If the driver’s foot is not on the accel-
erator pedal, the system activates the
brakes to decelerate smoothly as neces-
sary. If the vehicle ahead comes to a
stop, the vehicle decelerates to a stand-
still within the limitations of the system.
. If the driver’s foot is on the accelerator
pedal, the system moves the accelerator
pedal upward to assist the driver to
release the accelerator pedal.
When brake operation by the driver is
required:
The system alerts the driver by a warning
chime and blinking the vehicle ahead detec- tion indicator (orange). If the driver’s foot is
on the accelerator pedal after the warning,
the system moves the accelerator pedal
upward to assist the driver to switch to the
brake pedal.
NOTE:
.
The stop lights of the vehicle come on
when braking is performed by the DCA
system.
. When the brake operates, a noise may be
heard and/or vibration may be felt. This
is not a malfunction.
Overriding the system:
The following driver’s operation overrides
the system operation.
. When the driver depresses the accelera-
tor pedal even further while the system is
moving the accelerator pedal upward,
the DCA system control of the accel-
erator pedal is canceled.
. When the driver’s foot is on the accel-
erator pedal, the brake control by the
system is not operated.
. When the driver’s foot is on the brake
pedal, neither the brake control nor the
alert by the system operates.
. When the Intelligent Cruise Control (ICC)
system is set, the DCA system will be
cancelled.
Starting and driving5-87

JVS1238X
DCA SYSTEM DISPLAY AND IN-
DICATORS
The display is located between the speed-
ometer and tachometer.
1. Vehicle ahead detection indicator:Indicates whether it detects a vehicle in
front of you.
2. DCA system indicator: The indicator will appear in orange if
there is a malfunction in the DCA system.
DCA SYSTEM LIMITATIONS
WARNING
Listed below are the system limitations
of the DCA system. Failure to operate
the vehicle in accordance with these
system limitations could result in serious
injury or death.
.This system will not adapt automati-
cally to road conditions. Do not use
the system on roads with sharp
curves, or on icy roads, in heavy rain
or in fog.
. The DCA system will not apply brake
control while the driver’s foot is on
the accelerator pedal.
. As there is a performance limit to the
distance control function, never rely
solely on the DCA system. This sys-
tem does not correct careless, inat-
tentive or absent-minded driving, or
overcome poor visibility in rain, fog,
or other bad weather. Decelerate the
vehicle speed by depressing the brake
pedal, depending on the distance to
the vehicle ahead and the surround-
ing circumstances in order to main-
tain a safe distance between vehicles. .
The system may not detect the
vehicle in front of you in certain road
or weather conditions. To avoid ac-
cidents, never use the DCA system
under the following conditions:
— On roads with sharp curves
— On slippery road surfaces such as on ice or snow, etc.
— On off-road surfaces such as on sand or rock, etc.
— During bad weather (rain, fog, snow, etc.)
— When rain, snow or dirt adhere to the system sensor
— On steep downhill roads (fre- quent braking may result in over-
heating the brakes)
— On repeated uphill and downhill roads
— When towing a trailer or other vehicle
. In some road or traffic conditions, a
vehicle or object can unexpectedly
come into the sensor detection zone
and cause automatic braking. You
may need to control the distance
from other vehicles using the accel-
erator pedal. Always stay alert and
Starting and driving5-91

FEB WITH PEDESTRIAN DETEC-
TION SYSTEM OPERATION
The FEB with pedestrian detection system
operates at speeds above approximately 3
MPH (5 km/h).
For the pedestrian detection function, the
FEB with pedestrian detection system oper-
ates at speeds between 6 – 37 MPH (10 –
60 km/h).
If a risk of a forward collision with a vehicle is
detected, the FEB with pedestrian detection
system will firstly provide the warning to the
driver by blinking the vehicle ahead detection
indicator in the vehicle information display
and providing an audible alert. In addition,
the FEB with pedestrian detection system
pushes the accelerator pedal up. If the driver
releases the accelerator pedal, then the
system applies partial braking. If the driver
applies the brakes quickly and forcefully, but
the FEB with pedestrian detection system
detects that there is still the possibility of a
forward collision, the system will automati-
cally increase the braking force.
If the risk of a forward collision becomes
imminent and the driver does not take
action, the FEB with pedestrian detection
system issues the second visual (flashing)
and audible alert, and then automatically
applies harder braking.If a risk of a forward impact with a
pedestrian is detected, the FEB with pedes-
trian detection system issues the second
visual (flashing) and audible alert , and the
system will apply partial braking. If the driver
applies the brakes quickly and forcefully but
the FEB with pedestrian detection system
detects that there is still the possibility of a
forward impact with a pedestrian, the
system will automatically increase the brak-
ing force. If the risk of collision becomes
imminent and the driver does not take
action, the FEB with pedestrian detection
system automatically applies harder braking.
NOTE:
The vehicle’s stop lights come on when
braking is performed by the FEB with
pedestrian detection system.
Depending on vehicle speed and distance to
the vehicle or pedestrian ahead, as well as
driving and roadway conditions, the system
may help the driver avoid a forward collision
or may help mitigate the consequences of a
collision should one be unavoidable.
If the driver is handling the steering wheel,
accelerating or braking, the FEB with pe-
destrian detection system will function later
or will not function.
The automatic braking will cease under the
following conditions:
.
When the steering wheel is turned as far
as necessary to avoid a collision.
. When the accelerator pedal is depressed.
. When there is no longer a vehicle or
pedestrian detected ahead.
If the FEB with pedestrian detection system
has stopped the vehicle, the vehicle will
remain at a standstill for approximately 2
seconds before the brakes are released.
Starting and driving5-97

5-120Starting and driving
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).)
HILL START ASSIST SYSTEM

WARNING
If the engine is not running or is turned
off while driving, the power assist for
the steering will not work. Steering will
be harder to operate.
The power assisted steering uses a hydraulic
pump, driven by the engine, to assist steer-
ing.
If the engine stops or the drive belt breaks,
you will still have control of the vehicle.
However, much greater steering effort is
needed, especially in sharp turns and at low
speeds.
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 brakes function 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
Starting and driving5-123
POWER STEERING BRAKE SYSTEM

5-124Starting and driving
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.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
BRAKE ASSIST

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 andilluminates 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.
Starting and driving5-125
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 ........................................................... 8-33
Tire chains ................................................................ 8-34
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