2021 INFINITI QX80 stop start

5-116Starting and driving
The 4WD shift switch is used to select the
4WD mode depending on the driving condi-
tions. There are 3 types of drive modes
available, AUTO, 4HI and 4LO.
The 4WD shift switch electronically controls
the transfer case operation. Rotate the
switch to move between each mode, AUTO,
4H and 4L.
You must depress the 4WD shift switch to
select 4L, and the vehicle MUST be sta-
tionary and the shift lever in the N (Neutral)
position when changing into or out of 4L.
WARNING
.When parking, apply the parking
brake before stopping the engine
and make sure that the 4WD shift
indicator is on and the ATP warning
light turns off. Otherwise, the vehicle
could unexpectedly move even if the
automatic transmission is in the P
(Park) position.
. The 4LO and 4HI indicators must
stop blinking and the 4LO or 4HI
indicator must remain illuminated or
turn off before shifting the transmis-
sion into gear. If the shift lever is
shifted from the N (Neutral) position
to any other gear while the 4LO and
4HI indicators are blinking alter- nately, the vehicle may move unex-
pectedly.
CAUTION
.
Never shift the 4WD shift switch
between 4L and 4H while driving.
. The 4HI position provides greater
traction. Avoid excessive speed, as it
will cause increased fuel consumption
and higher oil temperatures, and
could damage drivetrain component.
Speeds over 62 MPH (100 km/h) in
4HI is not recommended.
. The 4LO position provides maximum
traction. Avoid raising vehicle speed
excessively, as the maximum speed is
approximately 31 MPH (50 km/h).
. When driving straight, shift the 4WD
shift switch to the AUTO or 4H
position. Do not move the 4WD shift
switch when making a turn or rever-
sing.
. Do not shift the 4WD shift switch
(between AUTO and 4H) while driv-
ing on steep downhill grades. Use the
engine brake and low automatic
transmission gears for engine brak-
ing. .
Do not operate the 4WD shift switch
(between AUTO and 4H) with the
rear wheels spinning.
. Do not drive on dry hard surface
roads in the 4HI or 4LO position.
Driving on dry hard surfaces in 4HI or
4LO may cause unnecessary noise
and tire wear. INFINITI recommends
driving in the AUTO position under
these conditions.
. The 4WD transfer case may not be
shifted between 4HI and 4LO at low
ambient temperatures and the 4LO
and 4HI indicators may blink even
when the 4WD shift switch is shifted.
After driving for a while you can
change the 4WD shift switch be-
tween 4H and 4L.
When driving on rough roads,
. Drive carefully according to the road
surface conditions.
When the vehicle is stuck,
. Place stones or wooden blocks under the
tires to free the vehicle.
. Set the 4WD shift switch to 4H or 4L.
. If it is difficult to free the vehicle, repeat
forward and backward movement to
increase the movement.

.If the vehicle is stuck deep in mud, tire
chains may be effective.
CAUTION
. Do not spin the tires excessively.
Tires will sink deep into the mud,
making it difficult to free the vehicle.
. Avoid shifting gears with the engine
running at high speeds as this may
cause malfunction.
SSD1048
4WD SHIFT SWITCH
.Shift the 4WD shift switch to either the
AUTO, 4H or 4L position, depending on
driving conditions.
. With the switch set to the AUTO posi-
tion, distribution of torque to the front
and rear wheels changes automatically,
depending on road conditions encoun-
tered [ratio; 0 : 100 (2WD) ?50 : 50
(4WD)]. This results in improved driving
stability.
. When the vehicle is stopped after mak-
ing a turn, you may feel a slight jolt after
the shift lever is shifted to N (Neutral) or
P (Park) position. This occurs because
the transfer clutch is released and not because of a malfunction.
CAUTION
.
When driving straight, shift the 4WD
shift switch to the AUTO or 4H
position. Do not move the 4WD shift
switch when making a turn or rever-
sing. If the 4WD shift switch is
operated while making a turn, accel-
erating or decelerating or if the
ignition switch is placed in the OFF
position while in the AUTO, 4H or 4L,
you may feel a jolt. This is not a
malfunction.
. Do not shift the 4WD shift switch
while driving on steep downhill
grades. Use the engine brake and
low automatic transmission gears
for engine braking.
. Do not operate the 4WD shift switch
with the rear wheels spinning.
. Before placing the 4WD shift switch
in the 4H position from AUTO,
ensure the vehicle speed is less than
62 MPH (100 km/h). Failure to do so
can damage the 4WD system.
. Never shift the 4WD shift switch
between 4L and 4H while driving.
Starting and driving5-117

If the 4WD warning light comes on, the
4WD shift indicator turns off.
High-temperature transfer case oil makes
the 4WD warning light blink rapidly (about
twice per second). If the warning light blinks
rapidly during operation, stop the vehicle in a
safe place immediately. Then if the light
turns off after a while, you can continue
driving.
A large difference between the diameters of
front and rear wheels will make the 4WD
warning light blink slowly (about once per
two seconds). Change the 4WD shift switch
to AUTO and do not drive fast.
CAUTION
.If the 4WD warning light comes on or
blinks slowly during operation or
rapidly after stopping the vehicle for
a while, have your vehicle checked as
soon as possible. It is recommended
you visit an INFINITI retailer for this
service.
. Shifting between 4HI and 4LO is not
recommended when the 4WD warn-
ing light turns on. .
When the 4WD warning light comes
on, the 2WD mode may be engaged
even if the 4WD shift switch is in
AUTO or 4H. Be especially careful
when driving. If corresponding parts
are malfunctioning, the 4WD mode
will not be engaged even if the 4WD
shift switch is shifted.
. Do not drive the vehicle in the 4HI or
4LO position on dry hard surface
roads. Driving on dry, hard surfaces
in 4HI or 4LO may cause unnecessary
noise, tire wear and increased fuel
consumption.
If the 4WD warning light turns on
when driving on dry hard surface
roads:
— in the AUTO or 4HI position, shift the 4WD shift switch to AUTO.
— in the 4LO position, stop the vehicle and shift the transmission
shift lever to the N (Neutral)
position and shift the 4WD shift
switch to AUTO.
. If the 4WD warning light is still on
after the above operation, have your
vehicle checked as soon as possible. It
is recommended you visit an INFINITI
retailer for this service. .
The transfer case may be damaged if
you continue driving with the warn-
ing light blinking.
Starting and driving5-119

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

SD1006MA
WARNING
.Do not stop or park the vehicle over
flammable materials such as dry
grass, waste paper or rags. They
may ignite and cause a fire.
. Never leave the engine running while
the vehicle is unattended.
. Do not leave children unattended
inside the vehicle. They could un-
knowingly activate switches or con-
trols. Unattended children could
become involved in serious accidents. .
To help avoid risk of injury or death
through unintended operation of the
vehicle and/or its systems, do not
leave children, people who require the
assistance of others or pets unat-
tended in your vehicle. Additionally,
the temperature inside a closed ve-
hicle on a warm day can quickly
become high enough to cause a sig-
nificant risk of injury or death to
people and pets.
. Safe parking procedures require that
both the parking brake be applied
and the transmission be placed in the
P (Park) position. Failure to do so could cause the vehicle to move
unexpectedly or roll away and result
in an accident.
. Make sure the automatic transmis-
sion shift lever has been pushed as far
forward as it can go and cannot be
moved without depressing the foot
brake pedal.
1. Firmly apply the parking brake.
2. Move the shift lever to the P (Park) position.
3. To help prevent the vehicle from rolling into the street when parked on a sloping
drive way, it is a good practice to turn the
wheels as illustrated.
.HEADED DOWNHILL WITH CURB:
Turn the wheels into the curb and move
the vehicle forward until the curb side
wheel gently touches the curb.
.HEADED UPHILL WITH CURB:
Turn the wheels away from the curb and
move the vehicle back until the curb side
wheel gently touches the curb.
.HEADED UPHILL OR DOWNHILL,NO CURB:
Turn the wheels toward the side of the
road so the vehicle will move away from
the center of the road if it moves.
Starting and driving5-121
PARKING/PARKING ON HILLS

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