2020 NISSAN ALTIMA engine

The brake system has two separate hy-
draulic circuits. If one circuit malfunctions,
you will still have braking at two wheels.
BRAKE PRECAUTIONS
Vacuum assisted brakes
The brake booster aids braking by using
engine vacuum. If the engine stops, you
can stop the vehicle by depressing the
brake pedal. However, greater foot pres-
sure on the brake pedal will be required to
stop the vehicle and stopping distance will
be longer.
Using the brakes
Avoid resting your foot on the brake pedal
while driving. This will overheat the brakes,
wear out the brake pads faster, and reduce
gas mileage.
To help reduce brake wear and to prevent
the brakes from overheating, reduce speed
and downshif t 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, becareful when braking, accelerating or
downshif ting. Abrupt braking or ac-
celerating 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 as-
sist for the brakes will not work. Brak-
ing will be harder.
Wet brakes
When the vehicle is washed or driven
through water, the brakes may get wet. As
a result, your braking distance will be lon-
ger and the vehicle may pull to one side
during braking.
To dry the brakes, drive the vehicle at a safe
speed while lightly pressing 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 that
you visit a NISSAN dealer for this service.
ANTI-LOCK BRAKING SYSTEM (ABS)
WARNING
∙ The 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 stop-
ping distances on slippery surfaces
will be longer than on normal sur-
faces even with ABS. Stopping dis-
tances 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 af- fect braking effectiveness.
BRAKE SYSTEM
Starting and driving5-169

– When replacing tires, install thespecified 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. For ad-
ditional information, refer to “Tire
and Loading Information label” in
the “Technical and consumer infor-
mation” section of this manual.
– For additional information, refer to “Wheels and tires” in the “Do-it-
yourself ” section of this manual.
The 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 pre-
vent 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 Anti-lock Braking System 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
distances.
Self-test feature
The Anti-lock Braking System (ABS) in-
cludes 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 mal-
function. If the computer senses a mal-
function, it switches the ABS off and illumi-
nates 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 ve-
hicle checked. It is recommended that you
visit a NISSAN dealer for this service.
Normal operation
The Anti-lock Braking System (ABS) oper-
ates at speeds abov
e3-6mph(5-
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 pulsa-
tion 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 op-
erating properly. However, the pulsation
may indicate that road conditions are haz-
ardous and extra care is required while
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.
5-170Starting and driving

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.The 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 output to reduce drive wheel slip based
on vehicle speed (traction control func-
tion).
∙ 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 fol- low the steered path despite in-
creased 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 can-
not prevent loss of vehicle control in all driv-
ing situations. When the VDC system operates, theindicator light in the instrument panel
flashes to 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 indi-
cates that the VDC system is working
properly.
∙ Adjust your speed and driving to the road conditions.
For additional information, refer to “Slip in-
dicator light” and “Vehicle Dynamic Control
(VDC) OFF indicator light” in the “Instru-
ments and controls” section of this manual.
If a malfunction occurs in the system,
the
indicator light comes on in the
instrument panel. The VDC system auto-
matically turns off when the indicator light
is on.
VEHICLE DYNAMIC CONTROL (VDC)
SYSTEM
Starting and driving5-171

The vehicle information display is used to
turn off the VDC system. When the VDC
system is turned off, the
indicator
light and if so equipped, the RAB system
warning light, AEB system warning light
and AEB with Pedestrian Detection system
warning light illuminate to indicate the
VDC, AEB, AEB with Pedestrian Detection,
and RAB systems are off.
When the VDC system is turned off in the
vehicle information display, the VDC sys-
tem still operates to prevent one drive
wheel from slipping by transferring power
to a non-slipping drive wheel. The
in-
dicator light flashes if this occurs. All other
VDC functions are off and the
indica-
tor 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.
The computer has a built-in diagnostic fea-
ture that tests the system each time you
start the engine and move the vehicle for-
ward 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 indica-
tion of a malfunction.
WARNING
∙ The VDC system is designed to help the driver maintain 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 al-
ways drive carefully.
∙ Do not modif y the vehicle’s suspen- sion. If suspension parts such as
shock absorbers, struts, springs, sta-
bilizer bars, bushings and wheels are
not NISSAN recommended for your
vehicle or are extremely deteriorated,
the VDC system may not operate
properly. This could adversely affect
vehicle handling performance, and
the
indicator light may flash or
the
indicator light may
illuminate. ∙ If brake related parts such as brake
pads, rotors and calipers are not
NISSAN recommended or are ex-
tremely deteriorated, the VDC system
may not operate properly and both
the
andindicator lights
may illuminate.
∙ If engine control related parts are not NISSAN recommended or are ex-
tremely deteriorated, both the
and theindicator lights may
illuminate.
∙ When driving on extremely inclined surfaces such as higher banked cor-
ners, the VDC system may not operate
properly and the
indicator light
may flash or the
indicator 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
indicator light may
flash or the
indicator light may
illuminate. This is not a malfunction.
Restart the engine af ter driving onto
a stable surface.
5-172Starting and driving

∙ If wheels or tires other than theNISSAN recommended ones are used,
the VDC system may not operate
properly and the
indicator light
may flash or the
indicator light
may illuminate.
∙ The VDC system is not a substitute for winter tires or tire chains on a snow
covered road.
BRAKE FORCE DISTRIBUTION
During braking while driving through turns,
the system optimizes the distribution of
force to each of the front and rear wheels
depending on the radius of the turn.
WARNING
∙ The VDC system is designed to helpthe driver maintain 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 al-
ways drive carefully. ∙ Do not modif y the vehicle’s suspen-
sion. If suspension parts such as
shock absorbers, struts, springs, sta-
bilizer bars, bushings and wheels are
not NISSAN recommended for your
vehicle or are extremely deteriorated,
the VDC system may not operate
properly. This could adversely affect
vehicle handling performance, and
the
indicator light may flash or
the
indicator light may
illuminate.
∙ If brake related parts such as brake pads, rotors and calipers are not
NISSAN recommended or are ex-
tremely deteriorated, the VDC system
may not operate properly and both
the
andindicator light may
illuminate.
∙ If engine control related parts are not NISSAN recommended or are ex-
tremely deteriorated, both the
and theindicator light may
illuminate. ∙ When driving on extremely inclined
surfaces such as higher banked cor-
ners, the VDC system may not operate
properly and the
indicator light
may flash or the
indicator 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
indicator light may
flash or the
indicator light may
illuminate. This is not a malfunction.
Restart the engine af ter driving onto
a stable surface.
∙ If wheels or tires other than the NISSAN recommended ones are used,
the VDC system may not operate
properly and the
indicator light
may flash or the
indicator light
may illuminate.
∙ The VDC system is not a substitute for winter tires or tire chains on a snow
covered road.
Starting and driving5-173

The chassis control is an electric control
module that includes the following func-
tions:∙ Intelligent Trace Control
∙ Active Ride Control
INTELLIGENT TRACE CONTROL
(I-TC)
This system senses driving based on the
driver’s steering and acceleration/braking
patterns, and controls brake pressure at
individual wheels to aid tracing at corners
and help smooth vehicle response.
The I-TC can be set to on (enabled) or off
(disabled) through the vehicle information
display “Settings” page. For additional infor-
mation, refer to “Vehicle information dis-
play” in the “Instruments and controls” sec-
tion of this manual.
When the VDC system is turned off, the I-TC
is also turned off.
WARNING
The I-TC may not be effective depend-
ing on the driving condition. Always
drive carefully and attentively. When the I-TC is operating, you may feel a
pulsation in the brake pedal and hear a
noise. This is normal and indicates that the
I-TC is operating properly.
Even if the I-TC is turned off, some functions
will remain on to assist the driver (for ex-
ample, avoidance scenes).
ACTIVE RIDE CONTROL (ARC)
This system senses upper body motion
(based on wheel speed information) and
controls engine torque and four wheel
brake pressure. This will enhance ride com-
fort in effort to restrain uncomfortable up-
per body movement when passing over
undulated road surfaces. This system
comes into effect above 25 mph (40 km/h).
When the VDC system is turned off, the ARC
is also turned off.
When the ARC is operating, you may hear
noise and sense slight deceleration. This is
normal and indicates that the ARC is oper-
ating properly.
WARNING
∙ Never rely solely on the hill start assist
system to prevent the vehicle from
moving backward on a hill. Always
drive carefully and attentively. De-
press the brake pedal when the ve-
hicle is stopped on a steep hill. Be es-
pecially careful when stopped on a hill
on frozen or muddy roads. Failure to
prevent the vehicle from rolling back-
wards may result in a loss of control of
the vehicle and possible serious injury
or death.
∙ The hill start assist system is not de- signed to hold the vehicle at a stand-
still 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 de-
press the brake pedal to prevent the
vehicle from rolling backwards. Fail-
ure to do so may result in a collision or
serious personal injury.
CHASSIS CONTROL HILL START ASSIST SYSTEM
5-174Starting and driving

SYSTEM MAINTENANCE
The sonar sensors1are located on the
rear bumper. Always keep the area near
the sonar sensors clean.
The sonar sensors may be blocked by tem-
porary ambient conditions such as splash-
ing water, mist or fog.
The blocked condition may also be caused
by objects such as ice, frost or dirt ob-
structing the sonar sensors.
Check for and remove objects obstructing
the area around the sonar sensors. Do not attach stickers (including transpar-
ent material), install accessories or apply
additional paint near the sonar sensors.
Do not strike or damage the area around
the sonar sensors. It is recommended that
you visit a NISSAN dealer if the area around
the sonar sensors is damaged due to a
collision.
FREEING A FROZEN DOOR LOCK
To prevent a door lock from freezing, apply
de-icer through the key hole. If the lock
becomes frozen, heat the key before in-
serting it into the key hole or use the re-
mote keyless entry function on the Intelli-
gent Key.
ANTIFREEZE
In the winter when it is anticipated that the
temperature will drop below 32°F (0°C),
check the antifreeze to assure proper win-
ter protection. For additional information,
refer to “Engine cooling system” in the “Do-
it-yourself ” section of this manual.
BATTERY
If the battery is not fully charged during
extremely cold weather conditions, the
battery fluid may freeze and damage the
battery. To maintain maximum efficiency,
the battery should be checked regularly.
For additional information, refer to “Battery”
in the “Do-it-yourself ” section of this
manual.
LSD3241
COLD WEATHER DRIVING
5-180Starting and driving

DRAINING OF COOLANT WATER
If the vehicle is to be lef t outside without
antifreeze, drain the cooling system, includ-
ing the engine block. Refill before operating
the vehicle. For additional information, refer
to “Changing engine coolant” in the “Do-it-
yourself ” section of this manual.
TIRE EQUIPMENT
1. SUMMER tires have a tread designed toprovide superior performance on dry
pavement. However, the performance
of these tires will be substantially re-
duced in snowy and icy conditions. If
you operate your vehicle on snowy or
icy roads, NISSAN recommends the use
of MUD & SNOW or ALL SEASON TIRES
on all four wheels. It is recommended
that you visit a NISSAN dealer for the tire
type, size, speed rating and availability
information.
2. For additional traction on icy roads, studded tires may be used. However,
some U.S. states and Canadian prov-
inces prohibit their use. Check local,
state and provincial laws before install-
ing studded tires. Skid and traction capabilities of studded
snow tires on wet or dry surfaces may be
poorer than that of non-studded snow
tires.
3. Tire chains may be used. For additional information, refer to “Tire chains” in the
“Do-it-yourself ” section of this manual.
SPECIAL WINTER EQUIPMENT
It is recommended that the following items
be carried in the vehicle during winter:
∙ A scraper and stiff-bristled brush to re- move ice and snow from the windows
and wiper blades.
∙ A sturdy, flat board to be placed under the jack to give it firm support.
∙ A shovel to dig the vehicle out of snow- drif ts.
∙ Extra washer fluid to refill the windshield-washer fluid reservoir.
DRIVING ON SNOW OR ICE
WARNING
∙ Wet ice (32°F, 0°C and freezing rain),very cold snow or ice can be slick and
very hard to drive on. The vehicle will
have much less traction or “grip” un-
der these conditions. Try to avoid driv-
ing on wet ice until the road is salted
or sanded.
∙ Whatever the condition, drive with caution. Accelerate and slow down
with care. If accelerating or down-
shif ting too fast, the drive wheels will
lose even more traction.
∙ Allow more stopping distance under these conditions. Braking should be
started sooner than on dry pavement.
∙ 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 steering
maneuvers.
Starting and driving5-181