brakes INFINITI QX50 2021 Owner's Guide

•The system may not detect the vehicle in
front of you in certain road or weather
conditions. To avoid accidents, never use
the DCA system under the following
conditions:
– On roads where the traffic is heavy or
there are sharp curves
– On slippery road surfaces such as on
ice or snow, etc.
– On off-road surfaces such as on sand
or rock, etc.
– During bad weather (rain, fog, snow,
etc.)
– When rain, snow or dirt adhere to the
sensor area of the front bumper
– On steep downhill roads (frequent
braking may result in overheating the
brakes)
– On repeated uphill and downhill roads
– When traffic conditions make it diffi-
cult to keep a proper distance be-
tween vehicles because of frequent
acceleration or deceleration
– When towing a trailer or other vehicle
– Interference by other radar sources •
In some road or traffic conditions, a ve-
hicle or object can unexpectedly come
into the sensor detection zone and cause
automatic braking. You may need to
control the distance from other vehicles
using the accelerator pedal. Always stay
alert and avoid using the DCA system
when it is not recommended in this
section.
The radar sensor will not detect the following
objects:
• Stationary and slow moving vehicles
• Pedestrians or objects in the roadway
• Oncoming vehicles in the same lane
• Motorcycles traveling offset in the travel lane
The following are some conditions in which
the sensor cannot detect the signals:
• When the snow or road spray from travel- ing vehicles reduces the sensor’s visibility
• When excessively heavy baggage is loaded in the rear seat or the luggage room of your
vehicle
Starting and driving5-113

WARNING
Failure to follow the warnings and instruc-
tions for proper use of the RAB system
could result in serious injury or death.
• The RAB system is a supplemental aid to
the driver. It is not a replacement for
proper driving procedures. Always use
the side and rear mirrors and turn and
look in the direction you will move before
and while backing up. Never rely solely
on the RAB system. It is the driver’s re-
sponsibility to stay alert, drive safely,
and be in control of the vehicle at all
times.
• Inclement weather or ultrasonic sources
such as an automatic car wash, a truck’s
compressed-air brakes or a pneumatic
drill may affect the function of the sys-
tem; this may include reduced perfor-
mance or a false activation.
• There is a limitation to the RAB system
capability. The RAB system is not effec-
tive in all situations.
The RAB system can assist the driver when
the vehicle is backing up and approaching
objects directly behind the vehicle. The RAB system detects obstacles behind
the vehicle using the parking sensors
O1lo-
cated on the rear bumper.
NOTE:
You can temporarily cancel the sonar func-
tion in the vehicle, but the RAB system will
continue to operate. For additional informa-
tion, see “Front and rear sonar system”
(P. 5-160).
LSD3559
REAR AUTOMATIC BRAKING (RAB)
5-118Starting and driving

RAB SYSTEM OPERATION
1RAB system warning light and RAB sys-
tem warning indicator
2Lower display buttons
3Center display (if so equipped) When the shift lever is in the R (Reverse)
position and the vehicle speed is less than
approximately 9 mph (15 km/h), the RAB
system operates.
If a risk of a collision with an obstacle is
detected when your vehicle is backing up, the
RAB system warning indicator will flash in the
vehicle information display, a red frame will
appear in the center display (for vehicles with
the Around View® Monitor system), and the
system will chime three times. The system will
then automatically apply the brakes. After
the automatic brake application, the driver
must depress the brake pedal to maintain
brake pressure.
NOTE:
• The brake lights of the vehicle come on
when braking is performed by the RAB
system.
• When the brakes operate, a noise may be heard. This is not a malfunction.
LSD3561
Starting and driving5-119

–Snow chains are used.
– Wheels or tires other than INFINITI
recommended are used.
– The brakes are cold at low ambient
temperatures or immediately after
driving has started.
– The braking force becomes poor due
to wet brakes after driving through a
puddle or washing the vehicle.
• Turn the RAB system off in the following
conditions to prevent the occurrence of
an unexpected accident resulting 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.
– Suspension parts other than those
designated as Genuine INFINITI
parts are used. (If the vehicle height
or the vehicle body inclination is
changed, the system may not detect
an obstacle correctly.)
– The vehicle is towing an object (if so
equipped). •
Excessive noise (e.g., audio system vol-
ume, an open vehicle window) will inter-
fere with the chime sound, and it may not
be heard.
SYSTEM MALFUNCTION
If the RAB system malfunctions, it will be
turned off automatically, the RAB system
warning light will illuminate, and the “System
fault” warning message will appear in the
vehicle information display.
Action to take
If the warning light illuminates, park the ve-
hicle in a safe location, turn the engine off,
and restart the engine. If the warning light
continues to illuminate, have the RAB system
checked. It is recommended that you visit an
INFINITI retailer for this service.
NOTE:
If the RAB system cannot be operated tem-
porarily, the RAB system warning light
blinks.
SYSTEM MAINTENANCE
Observe the following items to ensure proper
operation of the system:
• Always keep the parking sensors
O1clean.
• If the parking sensors are dirty, wipe them off with a soft cloth while being careful to
not damage them.
• Do not subject the area around the parking sensors
O1to strong impact. Also, do not
remove or disassemble the parking sensors.
If the parking sensors and peripheral areas
are deformed in an accident, etc., have the
sensors checked. It is recommended that
you visit an INFINITI retailer for this service.
LSD3559
5-122Starting and driving

SYSTEM OPERATION1. Vehicle ahead detection indicator
2. FEB with Pedestrian Detection emer-gency warning indicator 3. FEB with Pedestrian Detection system
warning light
The FEB with Pedestrian Detection system
operates at speeds above approximately 3
mph (5 km/h). For the pedestrian detection
function, the FEB with Pedestrian Detection
system operates at speeds between 6 – 37
mph (10 – 60 km/h).
If a risk of a forward collision is detected, the
FEB with Pedestrian Detection system will
firstly provide the warning to the driver by
flashing the vehicle ahead detection indicator
(yellow) in the vehicle information display and
providing an audible alert. If the driver applies
the brakes quickly and forcefully after the
warning, and the FEB with Pedestrian De-
tection system detects that there is still the
possibility of a forward collision, the system
will automatically increase the braking force.
If the driver does not take action, the FEB
with Pedestrian Detection system issues the
second visual (flashing) (red and white) and
audible warning. If the driver releases the
accelerator pedal, then the system applies
partial braking. If the risk of a collision be-
comes imminent, the FEB with Pedestrian
Detection system applies harder braking
automatically.
LSD3919
5-124Starting and driving

While the FEB with Pedestrian Detection
system is operating, you may hear the sound
of brake operation. This is normal and indi-
cates that the FEB with Pedestrian Detection
system is operating properly.
NOTE:
The vehicle’s brake lights come on when any
braking is performed by the FEB with Pedes-
trian Detection system.
Depending on vehicle speed and distance to
the vehicle or pedestrian ahead, as well as
driving and roadway conditions, the system
may help the driver avoid a forward collision
or may help mitigate the consequences if a
collision should be unavoidable. If the driver is
handling the steering wheel, accelerating or
braking, the FEB with Pedestrian Detection
system will function later or will not function.
The automatic braking will cease under the
following conditions:
• When the steering wheel is turned to avoida collision.
• When the accelerator pedal is depressed.
• When there is no longer a vehicle or a pe- destrian detected ahead. If the FEB with Pedestrian Detection system
has stopped the vehicle, the vehicle will re-
main at a standstill for approximately 2 sec-
onds before the brakes are released.
Starting and driving5-125

The brake system has two separate hydraulic
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 en-
gine vacuum. If the engine stops, you can
stop the vehicle by depressing the brake
pedal. However, greater foot pressure on the
brake pedal will be required to stop the ve-
hicle 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
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
• While driving on a slippery surface, be
careful when braking, accelerating or
downshifting. Abrupt braking or accel-
erating 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 assist for the
brakes will not work. Braking 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 longer 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 rotors are replaced, in order to
assure the best brake performance. This procedure is described in the INFINITI
Service Manual. It is recommended that you
visit an INFINITI retailer 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 main-
tain a safe distance from the vehicle in
front of you. Ultimately, the driver is re-
sponsible for safety.
• Tire type and condition may also affect
braking effectiveness.
– When replacing tires, install the
specified size of tires on all four
wheels.
BRAKE SYSTEM
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–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, see “Tire and Loading In-
formation label” (P. 8-28).
– For additional information, see
“Wheels and tires” (P. 8-27).
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 prevent 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 pre-
vent 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) 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 malfunction, it switches the ABS off
and illuminates the ABS warning light on the
instrument panel. The brake system then op-
erates 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 an
INFINITI retailer for this service.
Normal operation
The Anti-lock Braking System (ABS) operates
at speeds above3-6mph(5-10km/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 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 prop-
erly. However, the pulsation may indicate
that road conditions are hazardous 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.
Starting and driving5-153

If the chassis control system error warning
message appears in the vehicle information
display, it may indicate that the Active Ride
Control is not functioning properly. Have the
system checked as soon as possible. It is rec-
ommended that you visit an INFINITI retailer
for this service.
When the Active Ride Control is operating,
you may hear noise and sense slight decel-
eration. This is normal and indicates that the
Active Ride Control is operating properly.
WARNING
• Never rely solely on the hill start assist
system to prevent the vehicle from mov-
ing backward on a hill. Always 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 standstill
on a hill. Depress the brake pedal when
the vehicle is stopped on a steep hill. Fail-
ure 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 pre-
vent the vehicle from rolling backwards
on a hill under all load or road conditions.
Always be prepared to depress the brake
pedal to prevent the vehicle from rolling
backwards. Failure to do so may result in
a collision or serious personal injury. When the vehicle is stopped on a hill, the hill
start assist system automatically keeps the
brakes applied to help prevent the vehicle
from rolling backward in the time it takes the
driver to release the brake pedal and apply
the accelerator.
The hill start assist system will operate auto-
matically under the following conditions:
• The transmission is shifted to a forward or
reverse gear.
• The vehicle is stopped completely on a hill by applying the brake. The maximum hold-
ing time is 2 seconds. After 2 seconds the
vehicle will begin to roll back and the hill
start assist system will stop operating
completely.
The hill start assist system will not operate
when the shift lever is placed in the N (Neu-
tral), the Park button is pressed to place the
vehicle in the P (Park) position or on a flat and
level road.
The Hill Start Assist function status can be
checked in the “Chassis Control” mode in the
vehicle information display. For additional in-
formation, see “Vehicle information display”
(P. 2-19).
LSD3922
HILL START ASSIST SYSTEM
Starting and driving5-159

•Inclement weather or ultrasonic sources
such as an automatic car wash, a truck’s
compressed-air brakes or a pneumatic
drill may affect the function of the sys-
tem; this may include reduced perfor-
mance or a false activation.
• The system is not designed to prevent
contact with small or moving objects. Al-
ways move slowly. The system will not
detect small objects below the bumper or
on the ground.
• The system may not detect the following
objects: fluffy objects such as snow,
cloth, cotton, glass-wool, etc.; thin ob-
jects 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 system
will be deactivated automatically.
The system is not available until the condi-
tions no longer exist.
The sonar sensors may be blocked by tempo-
rary ambient conditions such as splashing
water, mist or fog. The blocked condition
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 sensors are located on the front
and rear bumpers. Always keep the area near
the sonar sensors clean.
The sonar sensors may be blocked by tempo-
rary ambient conditions such as splashing
water, mist or fog.
The blocked condition may also be caused by
objects such as ice, frost or dirt obstructing
the sonar sensors.
Check for and remove objects obstructing
the area around the sonar sensors.
LSD2993
5-164Starting and driving