2021 INFINITI QX80 brake

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

5-126Starting and driving
.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). The computer has a built-in diagnostic
feature that tests the system each time you
start the engine and move the vehicle
forward or in reverse at a slow speed. When
the self-test occurs, you may hear a “clunk”
noise and/or feel a pulsation in the brake
pedal. This is normal and is not an indication
of a malfunction.
WARNING
.
The VDC system is designed to help
improve driving stability but does not
prevent accidents due to abrupt
steering operation at high speeds or
by careless or dangerous driving
techniques. Reduce vehicle speed
and be especially careful when driving
and cornering on slippery surfaces
and always drive carefully.
. Do not modify the vehicle’s suspen-
sion. If suspension parts such as
shock absorbers, struts, springs, sta-
bilizer bars, bushings and wheels are
not INFINITI recommended for your
vehicle or are extremely deteriorated,
the VDC system may not operate
properly. This could adversely affect
vehicle handling performance, and
the VDC warning light
may
illuminate. .
If brake related parts such as brake
pads, rotors and calipers are not
INFINITI recommended or are extre-
mely deteriorated, the VDC system
may not operate properly and the
VDC warning light
may illumi-
nate.
. If engine control related parts are not
INFINITI recommended or are extre-
mely deteriorated, the VDC warning
light
may illuminate.
. When driving on extremely inclined
surfaces such as higher banked cor-
ners, the VDC system may not oper-
ate properly and the VDC warning
light
may illuminate. Do not drive
on these types of roads.
. When driving on an unstable surface
such as a turntable, ferry, elevator or
ramp, the VDC warning light
may
illuminate. This is not a malfunction.
Restart the engine after driving onto
a stable surface.
. If wheels or tires other than the
INFINITI recommended ones are
used, the VDC system may not oper-
ate properly and the VDC warning
light
may illuminate.
. The VDC system is not a substitute
for winter tires or tire chains on a

.Allow more stopping distance under
these conditions. Braking should be
started sooner than on dry pave-
ment.
. Allow greater following distances on
slippery roads.
. Watch for slippery spots (glare ice).
These may appear on an otherwise
clear road in shaded areas. If a patch
of ice is seen ahead, brake before
reaching it. Try not to brake while on
the ice, and avoid any sudden steer-
ing maneuvers.
. Do not use the cruise control on
slippery roads.
. Snow can trap dangerous exhaust
gases under your vehicle. Keep snow
clear of the exhaust pipe and from
around your vehicle.
ENGINE BLOCK HEATER (if so
equipped)
Engine block heaters are used to assist in
cold temperature starting.
The engine block heater should be used
when the outside temperature is 20°F
(−7°C) or lower.
To use the engine block heater
1. Turn the engine off.
2. Open the hood and unwrap the engine
block heater cord.
3. Plug the engine block heater cord into a grounded 3-wire, 3-pronged extension
cord.
4. Plug the extension cord into a Ground Fault Interrupt (GFI) protected,
grounded 110-volt AC (VAC) outlet.
5. The engine block heater must be plugged in for at least 2 - 4 hours, depending on
outside temperatures, to properly warm
the engine coolant. Use an appropriate
timer to turn the engine block heater on.
6. Before starting the engine, unplug and properly store the cord to keep it away
from moving parts.
WARNING
.Do not use your engine block heater
with an ungrounded electrical system
or a 2-pronged adapter. You can be
seriously injured by an electrical
shock if you use an ungrounded
connection.
. Disconnect and properly store the
engine block heater cord before starting the engine. Damage to the
cord could result in an electrical shock
and can cause serious injury.
. Use a heavy-duty 3-wire, 3-pronged
extension cord rated for at least 10A.
Plug the extension cord into a Ground
Fault Interrupt (GFI) protected,
grounded 110-VAC outlet. Failure
to use the proper extension cord or
a grounded outlet can result in a fire
or electrical shock and cause serious
personal injury.
Starting and driving5-129

6-4In case of emergency
cause a malfunction of the tire pres-
sure sensors.
CHANGING A FLAT TIRE
If you have a flat tire, follow the instructions
below.
Stopping the vehicle
1. Safely move the vehicle off the road andaway from traffic.
2. Turn on the hazard warning flashers.
3. Park on a level surface and apply the parking brake. Move the shift lever to the
P (Park) position.
4. Turn off the engine.
5. Raise the hood to warn other traffic, and to signal professional road assistance
personnel that you need assistance.
6. Have all passengers get out of the vehicle and stand in a safe place, away
from traffic and clear of the vehicle.
WARNING
.Make sure the parking brake is
securely applied and the automatic
transmission is in the P (Park) posi-
tion. .
Never change tires when the vehicle
is on a slope, ice or slippery areas.
This is hazardous.
. Never change tires if oncoming traf-
fic is close to your vehicle. Wait for
professional road assistance.
MCE0001A
Blocking wheels
Place suitable blocksat both the front and
back of the wheel diagonally opposite the
flat tire to prevent the vehicle from moving
when it is jacked up.
WARNING
Be sure to block the wheel as the vehicle
may move and result in personal injury.

6-12In case of emergency
industrial safety spectacles) and re-
move rings, metal bands, or any other
jewelry. Do not lean over the battery
when jump starting.
. Do not attempt to jump start a
frozen battery. It could explode and
cause serious injury.
. Your vehicle has an automatic engine
cooling fan. It could come on at any
time. Keep hands and other objects
away from it.
JVE0495X
WARNING
Always follow the instructions below.
Failure to do so could result in damage to
the charging system and cause personal
injury.
1. Remove the engine compartment cover, if necessary. See “Engine compartment
check locations” (P.8-3).
2. If the booster battery is in another vehicle
, position the two vehicles (and) to bring their batteries into close
proximity to each other. Do not allow the two vehicles to touch.
3. Apply parking brake. Move the shift lever to the P (Park) position. Switch off all
unnecessary electrical systems (light,
heater, air conditioner, etc.).
4. Remove vent caps on the battery (if so equipped). Cover the battery with a
firmly wrung out moist cloth
to reduce
explosion hazard.
5. Connect jumper cables in the sequence as illustrated (
???).

6-14In case of emergency
CAUTION
.Do not continue to drive if your
vehicle overheats. Doing so could
cause engine damage or a vehicle fire.
. To avoid the danger of being scalded,
never remove the radiator cap or
coolant reservoir cap while the en-
gine is still hot. When the radiator
cap or coolant reservoir cap is re-
moved, pressurized hot water will
spurt out, possibly causing serious
injury.
. Do not open the hood if steam is
coming out.
If your vehicle is overheating (indicated by an
extremely high temperature gauge reading),
or if you feel a lack of engine power, detect
abnormal noise, etc., take the following
steps:
1. Move the vehicle safely off the road, apply the parking brake and move the
shift lever to the P (Park) position.
Do not stop the engine.
2. Turn off the climate control. Open all the windows, move the heater or air condi-
tioner temperature control to maximum
hot and fan control to high speed. 3. If engine overheating is caused by climb-
ing a long hill on a hot day, run the engine
at a fast idle (approximately 1,500 rpm)
until the temperature gauge indication
returns to normal.
4. Get out of the vehicle. Look and listen for steam or coolant escaping from the
radiator before opening the hood. (If
steam or coolant is escaping, turn off the
engine.) Do not open the hood further
until no steam or coolant can be seen.
5. Open the engine hood.
WARNING
If steam or water is coming from the
engine, stand clear to prevent getting
burned.
6. Visually check drive belts for damage or looseness. Also check if the cooling fan is
running. The radiator hoses and radiator
should not leak water. If coolant is
leaking or the cooling fan does not run,
stop the engine.
WARNING
Be careful not to allow your hands, hair,
jewelry or clothing to come into contact
with, or get caught in, engine belts or the
engine cooling fan. The engine cooling
fan can start at any time.
7. After the engine cools down, check the coolant level in the reservoir tank with
the engine running. Add coolant to the
reservoir tank if necessary. Have your
vehicle repaired. It is recommended you
visit an INFINITI retailer for this service.
IF YOUR VEHICLE OVERHEATS