brake sensor NISSAN SENTRA 1999 B14 / 4.G Owners Manual

Page 123 of 223

increases wear on the brake linings and
pads, and reduces 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
cWhile driving on a slippery surface,
be careful when braking, accelerat-
ing or downshifting. Abrupt braking
or accelerating could cause the
wheels to skid and result in an acci-
dent.
cIf the engine is not running or is
turned off while driving, the power
assist for the brakes will not work.
Braking will be harder.
The anti-lock brake system controls the
brakes at each wheel so the wheels do not
lock when braking abruptly 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 wheel
lockup, the system helps the driver maintain
steering control and helps to minimize swerv-
ing and spinning on slippery surfaces.
Using the System
Depress the brake pedal and hold it down.
WARNING
Do not pump the brake pedal. Doing so
may result in increased stopping dis-
tances.
Normal operation
The anti-lock brake system does not oper-
ate at speeds below 3 to 6 MPH (5 to 10
km/h). The speeds vary according to road
conditions. When the anti-lock system
senses that one or more wheels are close to
locking up, the actuator (under the hood)
rapidly applies and releases hydraulic pres-
sure (like pumping the brakes very quickly).While the actuator is working, you may feel
a pulsation in the brake pedal and hear a
noise or vibration from the actuator under
the hood. This is normal and indicates that
the anti-lock system is working properly.
However, the pulsation may indicate that
road conditions are hazardous and extra
care is required while driving.
Self-test feature
The anti-lock brake system is sophisticated,
with electronic sensors, electric pumps, and
hydraulic solenoids controlled by a com-
puter. The computer has a built-in diagnos-
tic 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 is not an indica-
tion of any malfunction. If the computer
senses any malfunction, it switches the anti-
lock brake system OFF and turns on the
ABS brake warning light in the dashboard.
The brake system then operates normally,
but without anti-lock assistance.
If the light comes on during the self-test or
while driving, take the vehicle to an autho-
rized NISSAN dealer for repair.
ANTI-LOCK BRAKE SYSTEM
(ABS) (if so equipped)
5-18Starting and driving
ZX