2023 NISSAN ALTIMA brake sensor

•Once the automatic brake control
operates, it does not operate again if
the vehicle approaches the same
obstacle.
• The automatic brake control can only
operate for a short period of time.
Therefore, the driver must depress
the brake pedal.
• In the following situations, the RAB
system may not operate properly or
may not function sufficiently:
– The vehicle is driven in bad
weather (rain, fog, snow, etc.).
– The vehicle is driven on a steep
hill.
– The vehicle’s posture is changed
(e.g., when driving over a bump).
– The vehicle is driven on a slippery
road.
– The vehicle is turned sharply by
turning the steering wheel fully.
– Snow chains are used. –
Wheels or tires other than NISSAN
recommended are used.
– The brakes are cold at low ambi-
ent temperatures or immediately
af ter driving has started.
– The braking force becomes poor
due to wet brakes af ter driving
through a puddle or washing the
vehicle.
• Turn the RAB system off in the follow-
ing conditions to prevent the occur-
rence of an unexpected accident re-
sulting from sudden system
operation:
– The vehicle is towed.
– The vehicle is carried on a flatbed
truck.
– The vehicle is on the chassis
dynamometer.
– The vehicle drives on an uneven
road surface.
– The vehicle is towing an object (if
so equipped). –
Suspension parts other than
those designated as Genuine
NISSAN parts are used. (If the ve-
hicle height or the vehicle body in-
clination is changed, the system
may not detect an obstacle
correctly.)
– If the vehicle is using an accessory
like a bike rack, or cargo carrier
that blocks the sensors.
• Excessive noise (e.g., audio system
volume, an open vehicle window) will
interfere with the chime sound, and it
may not be heard.
Starting and driving5-133

•Tire type and condition may also af-
fect 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. For ad-
ditional information, see “Tire and
Loading Information label”
(P. 10-14).
– For additional information, see
“Wheels and tires” (P. 8-29).
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.
5-174Starting 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 ve-
hicle 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 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 can-
not prevent loss of vehicle control in all driv-
ing situations.
When the VDC system operates, the
indicator 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, see “Slip indica-
tor light” (P. 2-16) and “Vehicle Dynamic Con-
trol (VDC) OFF indicator light” (P. 2-17).
If a malfunction occurs in the system, the
indicator light comes on in the instru-
ment panel. The VDC system automatically
turns off when the indicator light is on.
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.
VEHICLE DYNAMIC CONTROL (VDC)
SYSTEM
Starting and driving5-175

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 seri-
ous injury or death.
• The system is deactivated at speeds
above 6 mph (10 km/h). It is reacti-
vated 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 af-
fect the function of the system; this
may include reduced performance or
a false activation.
• The system is not designed to pre-
vent contact with small or moving
objects. Always move slowly. The
system will not detect small objects
below the bumper or on the ground.
• The system may not detect the fol-
lowing objects: fluff y objects such as
snow, cloth, cotton, glass-wool, etc.;
thin objects such as rope, wire and
chain, etc.; or wedge-shaped objects. •
The system may not detect objects
at speeds above 3 mph (5 km/h) and
may not detect certain angular or
moving objects.
• Do not attach stickers (including
transparent material), install acces-
sories, or apply anything blocking
the sensors. These conditions may
reduce the ability of the system.
SYSTEM TEMPORARILY
UNAVAILABLE
When sonar blockage is detected, the sys-
tem will be deactivated automatically.
The system is not available until the condi-
tions no longer exist.
The sonar sensors may be blocked by tem-
porary ambient conditions such as splash-
ing water, mist or fog. The blocked condi-
tion may also be caused by objects such as
ice, frost or dirt obstructing the sonar
sensors.
Action to take:
When the above conditions no longer exist,
the system will resume automatically.
SYSTEM MAINTENANCE
The sonar sensorsO1are 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.
LSD3241
5-184Starting and driving

WARNING
• The use of tires other than those rec-
ommended or the mixed use of tires
of different brands, construction
(bias, bias-belted or radial), or tread
patterns can adversely affect the
ride, braking, handling, Vehicle Dy-
namic Control (VDC) system, ground
clearance, body-to-tire clearance,
tire chain clearance, speedometer
calibration, headlight aim and bum-
per height. Some of these effects
may lead to accidents and could re-
sult in serious personal injury.
• If your vehicle was originally
equipped with four tires that were
the same size and you are only re-
placing two of the four tires, install
the new tires on the rear axle. Placing
new tires on the front axle may cause
loss of vehicle control in some driving
conditions and cause an accident
and personal injury. •
If the wheels are changed for any
reason, always replace with wheels
which have the same off-set dimen-
sion. Wheels of a different off-set
could cause premature tire wear, de-
grade vehicle handling characteris-
tics, affect the VDC system and/or in-
terference with the brake discs. Such
interference can lead to decreased
braking efficiency and/or early brake
pad wear. For additional information
on wheel off-set dimensions, see
“Wheels and tires” (P. 10-10).
• When using a wheel without the
TPMS, such as the spare tire, the
TPMS will not function and the low
tire pressure warning light will flash
for approximately 1 minute. The light
will remain on af ter 1 minute. Have
your tires replaced and/or TPMS sys-
tem reset as soon as possible. It is
recommended that you visit a
NISSAN dealer for this service.
• Replacing tires with those not origi-
nally specified by NISSAN could af-
fect the proper operation of the
TPMS.
• The TPMS sensor may be damaged if
it is not handled correctly. Be careful
when handling the TPMS sensor. •
When replacing the TPMS sensor, the
ID registration may be required. It is
recommended that you visit a
NISSAN dealer for ID registration.
• Do not use a valve stem cap that is
not specified by NISSAN. The valve
stem cap may become stuck.
• Be sure that the valve stem caps are
correctly fitted. Otherwise the valve
may be clogged up with dirt and
cause a malfunction or loss of
pressure.
• Do not install a damaged or de-
formed wheel or tire even if it has
been repaired. Such wheels or tires
could have structural damage and
could fail without warning.
• The use of retread tires is not
recommended.
• For additional information regarding
tires, refer to “Important Tire Safety
Information” (US) or “Tire Safety In-
formation” (Canada) in the Warranty
Information Booklet.
Do-it-yourself8-41

Outside the vehicle
The maintenance items listed here should
be performed from time to time, unless
otherwise specified.
Doors and engine hood:
Check that the
doors and engine hood operate properly.
Also ensure that all latches lock securely. Lu-
bricate hinges, latches, latch pins, rollers and
links if necessary. Make sure that the sec-
ondary latch keeps the hood from opening
when the primary latch is released.
When driving in areas using road salt or
other corrosive materials, check lubrica-
tion frequently.
Check that the gas strays or struts properly
and securely hold the hood, trunk, or rear
hatch in the fully open position. If the hood,
trunk, or rear hatch is not held open, have
the gas stays or struts replaced.
Lights*: Clean the headlights on a regular
basis. Make sure that the headlights, stop
lights, tail lights, turn signal lights, and other
lights are all operating properly and in-
stalled securely. Also check headlight aim.
Road wheel nuts (lug nuts)*: When check-
ing the tires, make sure no wheel nuts are
missing, and check for any loose wheel
nuts. Tighten if necessary. Tire rotation*:
Rotate tires at the specified
interval shown in the maintenance
schedule.
Tires*: Check the pressure with a gauge
of ten and always prior to long distance
trips. If necessary, adjust the pressure in all
tires, including the spare, to the pressure
specified. Check carefully for damage, cuts
or excessive wear.
Tire Pressure Monitoring System (TPMS)
tire pressure sensor: It is recommended
that you replace the TPMS tire pressure
sensor assembly when the tires are re-
placed due to wear or age.
Wheel alignment and balance: If the ve-
hicle should pull to either side while driving
on a straight and level road, or if you detect
uneven or abnormal tire wear, there may
be a need for wheel alignment. If the steer-
ing wheel or seat vibrates at normal high-
way speeds, wheel balancing may be
needed.
For additional information regarding tires,
refer to “Important Tire Safety Information”
(US) or “Tire Safety Information” (Canada) in
the Warranty Information Booklet.
Windshield: Clean the windshield on a
regular basis. Check the windshield at least
every six months for cracks or other dam- age. Have a damaged windshield repaired
by a qualified repair facility. It is recom-
mended that you have a damaged wind-
shield repaired by a NISSAN dealer, or a
NISSAN Certified Collision Center. To locate
a collision center in your area, refer to
http://collision.nissanusa.com.
Windshield wiper blades*:
Check for
cracks or wear if they do not wipe properly.
Inside the vehicle
The maintenance items listed here should
be checked on a regular basis, such as
when performing scheduled maintenance,
cleaning the vehicle, etc.
Accelerator pedal: Check the pedal for
smooth operation and make sure the
pedal does not catch or require uneven
effort. Keep the floor mat away from the
pedal.
Brake pedal: Check the pedal for smooth
operation. If the brake pedal suddenly goes
down further than normal, the pedal feels
spongy or the vehicle seems to take longer
to stop, have your vehicle checked imme-
diately. It is recommended that you visit a
NISSAN dealer for this service. Keep the
floor mat away from the pedal.
Maintenance and schedules9-3