2020 NISSAN LEAF brake sensor

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 ve-
hicle in front of you. Ultimately, the
driver is responsible for safety.
• Tire type and condition may also af-
fect braking effectiveness.
– When replacing tires, install the
specified size of tires on all four
wheels.
– For additional information, refer
to “Wheels and tires” in the “Main-
tenance and do-it-yourself ” sec-
tion 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 dis-
tances.
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 push
the power switch in the READY to drive po-
sition 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 certified LEAF dealer for this
service.
Normal operation
The Anti-lock Braking System (ABS) oper-
ates at speeds above 3 to 6 mph (5 to 10
km/h). The speed varies according to road
conditions.
Starting and driving5-159

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.
WARNING
The Brake Assist is only an aid to assist
braking operation and is not a collision
warning or avoidance device. It is the
drivers 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 drive wheel on the
same axle that is not slipping.
• Controls brake pressure and traction motor output to reduce drive wheel slip
based on vehicle speed (traction control
function).
• Controls brake pressure at individual wheels and traction motor 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 main-
tain control of the vehicle, but it cannot
prevent loss of vehicle control in all driving
situations.
When the VDC system operates, the
indicator light in the instrument panel
flashes. When the indicator light flashes,
note the following items: • 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 according 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 illuminates in the ve-
hicle information display. The VDC system
automatically turns off when this indicator
light is lit.
The vehicle information display is used to
turn off the VDC system. The VDC OFF indi-
cator light
illuminates to indicate that
the VDC system is off. When the vehicle
information display 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 wheel.
VEHICLE DYNAMIC CONTROL (VDC)
SYSTEM
5-160Starting and driving

may indicate that the Intelligent Trace Con-
trol is not functioning properly. Have the
system checked as soon as possible. It is
recommended that you visit a NISSAN cer-
tified LEAF dealer for this service.
WARNING
The Intelligent Trace Control may not
be effective depending on the driving
condition. Always drive carefully and
attentively.
When the Intelligent Trace Control is oper-
ating, you may feel a pulsation in the brake
pedal, hear a noise and sense slight decel-
eration. This is normal and indicates that
the Intelligent Trace Control is operating
properly.
Even if the Intelligent Trace Control is
turned off, some functions will remain on to
assist the driver (for example, avoidance
scenes).
INTELLIGENT RIDE CONTROL
This system senses upper body motion
(based on wheel speed information) and
controls motor torque. This will enhance
ride comfort in effort to restrain uncom-
fortable upper 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 in the
vehicle information display, the Intelligent
Ride Control is also turned off.
WARNING
The Intelligent Ride Control may not be
effective depending on the driving con-
dition. Always drive carefully and at-
tentively.
When the Intelligent Ride Control is operat-
ing, you may hear a noise and sense slight
deceleration. This is normal and indicates
that the Intelligent Ride Control is operat-
ing properly.
If the “Chassis Control System Error: See
Owner’s Manual” warning message ap-
pears in the vehicle information display, it
may indicate that the Intelligent Ride Con-
trol is not functioning properly. Have the
system checked as soon as possible. It is
recommended that you visit a NISSAN cer-
tified LEAF dealer for this service. The sonar (parking sensor) system sounds
a tone to inform the driver of obstacles
near the bumper.
When the “DISPLAY” key is ON, the sonar
view will automatically appear in the meter.
WARNING
• The RSS is a convenience but it is not
a substitute for proper parking.
• The driver is always responsible for
safety during parking and other ma-
neuvers. Always look around and
check that it is safe to do so before
parking.
LSD3247
REAR SONAR SYSTEM (RSS)
Starting and driving5-163

•Read and understand the limitations
of the RSS as contained in this sec-
tion. The colors of the sonar indicator
and the distance guide lines in the
rear view indicate different distances
to the object.
• 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 RSS is designed as an aid to the
driver in detecting large stationary
objects to help avoid damaging the
vehicle.
• The RSS is not designed to prevent
contact with small or moving ob-
jects. Always move slowly. The sys-
tem will not detect small objects be-
low the bumper, and may not detect
objects close to the bumper or on the
ground.
• The RSS may not detect the following
objects: fluff y objects such as snow,
cloth, cotton, glass, wool, etc., and
thin objects such as rope, wire and
chain, etc., or wedge-shaped objects. If your vehicle sustains damage to the rear
bumper fascia, leaving it misaligned or
bent, the sensing zone may be altered
causing inaccurate measurement of ob-
stacles or false alarms.
CAUTION
• Excessive noise (such as audio sys-
tem volume or an open vehicle win-
dow) will interfere with the tone and
it may not be heard.
• Keep the sonar sensors (located on
the bumper fascia) free from snow,
ice and large accumulations of dirt.
Do not clean the sensors with sharp
objects. If the sensors are covered,
the accuracy of the sonar function
will be diminished.
SYSTEM OPERATION
The system informs with a visual and au-
dible alert of rear obstacles when the shif t
lever is in the R (Reverse) position. Sonar Operation Table
RR Sensor
Range Sound Display Px †
Roo
Nx † Dx †
o – Display/Beep when detect
† – Display on camera view
x – No Display and Beep
The system is deactivated at speeds above
6 mph (10 km/h). It is reactivated at lower
speeds.
While the vehicle is moving the audible alert
will stop af ter 3 seconds when an obstacle
is detected by only the corner sensor and
distance does not change. The audible
alert will also stop when the obstacle
moves away from the vehicle. At any time
the lef t side button of the steering wheel (
buttons) is available to cancel the au-
dible alert.
5-164Starting and driving

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.
• Read and understand the limitations
of the sonar system as contained in
this section. Inclement weather may
affect the function of the sonar sys-
tem; this may include reduced per-
formance or a false activation.
• 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.
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 sen-
sors.
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.
LSD2843
Starting and driving5-167

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.WARNING
• Never rely solely on the hill start as-
sist system to prevent the vehicle
from moving backward on a hill. Al-
ways drive carefully and attentively.
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 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 may not prevent
the vehicle from rolling backwards
on a hill under all load or road condi-
tions. Always be prepared to depress
the brake pedal to prevent the ve-
hicle 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.
Hill start assist will operate automatically
under the following conditions:
• The shif t lever is placed in the D (Drive), B
mode, or R (Reverse) position.
• The vehicle is stopped completely on a hill by applying the brake.
The maximum holding time is 2 seconds.
Af ter 2 seconds the vehicle will begin to roll
back and hill start assist will stop operating
completely.
Hill start assist will not operate when the
shif t lever is placed in the N (Neutral) or P
(Park) position or on a flat and level road.
HILL START ASSIST SYSTEM
5-168Starting and driving

•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/shoe wear. For additional infor-
mation on wheel-off set dimensions,
refer to “Wheels and tires” in the
“Technical and consumer informa-
tion” section of this manual.
• When replacing a wheel without the
TPMS such as the spare tire, the TPMS
will not function when a wheel is re-
placed, 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. It is recommended that you
visit a NISSAN certified LEAF 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 certified LEAF 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 tire 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.Wheel balance
Unbalanced wheels may affect vehicle
handling and tire life. Even with regular use,
wheels can get out of balance. Therefore,
they should be balanced as required.
Wheel balance service should be per-
formed with the wheels off the vehicle.
Spin balancing the wheels on the vehicle
could lead to mechanical damage.
For additional information regarding tires,
refer to “Important Tire Safety Information”
(US) or “Tire Safety Information” (Canada) in
the Warranty Information Booklet.
Care of wheels
For additional information on care of
wheels, refer to “Cleaning exterior” in the
“Appearance and care” section of this
manual.
EMERGENCY TIRE PUNCTURE
REPAIR KIT
The emergency tire puncture repair kit
(Emergency Tire Sealant) is supplied with
the vehicle instead of a spare tire. It can be
used to temporarily repair minor tire punc-
tures.
Maintenance and do-it yourself8-39