abs sensor NISSAN SENTRA 2017 B17 / 7.G Owners Manual

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 tech-
niques. It can help maintain vehicle con-
trol during braking on slippery surfaces.
Remember that stopping distances on
slippery surfaces will be longer than on
normal surfaces even with ABS. Stop-
ping 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 ve-
hicle 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. For additional in-
formation, refer to “Tire and Loading
Information label” in the “Technical
and consumer information” 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 rota-
tion speed at each wheel and varies the brake
fluid pressure to prevent each wheel from locking
and sliding. By preventing each wheel from lock-
ing, the system helps the driver maintain steering
control and helps to minimize swerving and spin-
ning on slippery surfaces.
Using the system
Depress the brake pedal and hold it down. De-
press the brake pedal with firm steady pressure,
but do not pump the brakes. The ABS will oper-
ate 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 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 malfunc-
tion, it switches the ABS off and illuminates 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 that you visit a
NISSAN dealer for this service.
Normal operation
The ABS operates at speeds above3-6mph(5
- 10 km/h). The speed varies according to road
conditions.
Starting and driving5-73

When the ABS senses that one or more wheels
are close to locking up, the actuator rapidly ap-
plies and releases hydraulic pressure. 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 indicate that road
conditions are hazardous and extra care is re-
quired while driving.
BRAKE ASSIST
When the force applied to the brake pedal ex-
ceeds a certain level, the brake assist is activated
generating greater braking force than a conven-
tional 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 driv-
ers 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 per-
form 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 function) .
● Controls brake pressure at individual wheels
and engine output to help the driver maintain
control of the vehicle in the following condi-
tions:
– understeer (vehicle tends to not follow the steered path despite increased steer-
ing 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
indi-
cator 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 indicates that the
VDC system is working properly.
● Adjust your speed and driving to the road
conditions.
For additional information, refer to “Slip indicator
light” and ”VDC off indicator light” in the ”Instru-
ments and controls” section.
If a malfunction occurs in the system, the
indicator light comes on in the instrument panel.
The VDC system automatically turns off when the
indicator light is off.
The VDC OFF switch is used to turn off the VDC
system. The
indicator illuminates to indi-
cate 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
indicator flashes if this occurs. All other VDC
functions are off and the
indicator will not
flash.
VEHICLE DYNAMIC CONTROL (VDC)
SYSTEM
5-74Starting and driving