brakes INFINITI Q50 HYBRID 2018 User Guide

WARNING
Failure to follow the warnings and
instructions for proper use of the DCA
system could result in serious personal
injury or death.
.Always drive carefully and atten-
tively when using the DCA system.
Read and understand the Owner’s
Manual thoroughly before using the
DCA system. To avoid serious injury
or death, do not rely on the system to
prevent accidents or to control the
vehicle’s speed in emergency situa-
tions. Do not use the DCA system
except in appropriate road and traffic
conditions.
. This system is only an aid to assist the
driver 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 vehicle
at all times.
. As there is a performance limit to the
distance control function, never rely
solely on the DCA system. This sys-
tem does not correct careless, inat-
tentive or absent-minded driving, or
overcome poor visibility in rain, fog,
or other bad weather. Decelerate the vehicle speed by depressing the brake
pedal, depending on the distance to
the vehicle ahead and the surround-
ing circumstances in order to main-
tain a safe distance between vehicles.
. Always pay attention to the opera-
tion of the vehicle and be ready to
manually decelerate to maintain the
proper following distance. The DCA
system may not be able to decelerate
the vehicle under some circum-
stances.
. This system only brakes and moves
the accelerator pedal upward to help
assist the driver to maintain a follow-
ing distance from the vehicle ahead.
Acceleration should be operated by
the driver.
. The DCA system does not control
vehicle speed or warn you when you
approach stationary and slow moving
vehicles. You must pay attention to
vehicle operation to maintain proper
distance from vehicles ahead.
. The DCA system automatically de-
celerates your vehicle to help assist
the driver to maintain a following
distance from the vehicle ahead.
Manually brake when deceleration is
required to maintain a safe distance
upon sudden braking by the vehicle ahead or when a vehicle suddenly
appears in front of you. Always stay
alert when using the DCA system.
. If the vehicle ahead comes to a stop,
the vehicle decelerates to a standstill
within the limitations of the system.
The system will cancel with a warning
chime once it judges that the vehicle
has come to a standstill. To prevent
the vehicle from moving, the driver
must depress the brake pedal.
Starting and driving5-93
DISTANCE CONTROL ASSIST
(DCA) (if so equipped)

5-94Starting and driving
JVS1123X
The DCA system is intended to assist the
driver in keeping a following distance from
the vehicle ahead traveling in the same lane
and direction.
If the radar sensor
detects a slower
moving vehicle ahead, the system will reduce
the vehicle speed to help assist the driver to
maintain a following distance.
The system automatically controls the throt-
tle and applies the brakes (up to approxi-
mately 40% of vehicle braking power) if
necessary.
The detection range of the sensor is approxi-
mately 650 ft (200 m) ahead.

JVS0844X
Dynamic driver assistance switch
Driver assist system forward indicator
(green) (on the vehicle information dis-
play)
Vehicle ahead detection indicator (on
the vehicle information display)
Lower display
DCA SYSTEM OPERATION
WARNING
Failure to follow the warnings and
instructions for proper use of the DCA
system could result in serious personal
injury or death.
.When the vehicle ahead detection
indicator is not illuminated, system
will not control the vehicle or warn
the driver.
. Never place your foot under the
brake pedal. Your foot may be caught
when the system controls the brake.
. Depending on the position of the
accelerator pedal, the system may
not be able to assist the driver to
release the accelerator pedal appro-
priately.
The DCA system brakes and moves the
accelerator pedal upward according to the
distance from and the relative speed of the
vehicle ahead to help assist the driver in
maintaining a following distance. The sys-
tem will decelerate as necessary and if the
vehicle ahead comes to a stop, the vehicle
decelerates to a standstill. However, the
DCA system can only apply up to approxi-
Starting and driving5-95

5-96Starting and driving
mately 40% of the vehicle’s total braking
power. If a vehicle moves into the traveling
lane ahead or if a vehicle traveling ahead
rapidly decelerates, the distance between
vehicles may become closer because the
DCA system cannot decelerate the vehicle
quickly enough. If this occurs, the DCA
system will sound a warning chime and blink
the system display to notify the driver to
take necessary action.
See “Approach warning” (P.5-97).
JVS0244X
System set display with a vehicle ahead
System set display without a vehicle
ahead
System set display with a vehicle ahead
(brake operation is necessary)
The DCA system helps assist the driver to
keep a following distance to the vehicle
ahead by braking and moving the accelera-
tor pedal upward in the normal driving
condition.
When a vehicle ahead is detected:
The vehicle ahead detection indicator ap-
pears. When the vehicle approaches a vehicle
ahead:
.
If the driver’s foot is not on the accel-
erator pedal, the system activates the
brakes to decelerate smoothly as neces-
sary. If the vehicle ahead comes to a
stop, the vehicle decelerates to a stand-
still within the limitations of the system.
. If the driver’s foot is on the accelerator
pedal, the system moves the accelerator
pedal upward to assist the driver to
release the accelerator pedal.

5-100Starting and driving
front of you.
DCA SYSTEM LIMITATIONS
WARNING
Listed below are the system limitations
of the DCA system. Failure to operate
the vehicle in accordance with these
system limitations could result in serious
injury or death.
.This system will not adapt automati-
cally to road conditions. Do not use
the system on roads with sharp
curves, or on icy roads, in heavy rain
or in fog.
. The DCA system will not apply brake
control while the driver’s foot is on
the accelerator pedal.
. As there is a performance limit to the
distance control function, never rely
solely on the DCA system. This sys-
tem does not correct careless, inat-
tentive or absent-minded driving, or
overcome poor visibility in rain, fog,
or other bad weather. Decelerate the
vehicle speed by depressing the brake
pedal, depending on the distance to
the vehicle ahead and the surround-
ing circumstances in order to main-
tain a safe distance between vehicles. .
The system may not detect the
vehicle in front of you in certain road
or weather conditions. To avoid ac-
cidents, never use the DCA system
under the following conditions:
— On roads with sharp curves
— On slippery road surfaces such as on ice or snow, etc.
— During bad weather (rain, fog, snow, etc.)
— When rain, snow or dirt adhere to the system sensor
— On steep downhill roads (fre- quent braking may result in over-
heating the brakes)
— On repeated uphill and downhill roads
. In some road or traffic conditions, a
vehicle 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 accel-
erator 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 follow-
ing 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
traveling vehicles reduces the sensor’s
visibility
. When excessively heavy baggage is
loaded in the rear seat or the trunk room
of your vehicle

JVS0846X
FEB system warning light (on the
instrument panel)
Indicators and warnings (on the vehicle
information display)
Driver assist system forward indica-
tor
Vehicle ahead detection indicator
Lower display
FEB SYSTEM OPERATION
The FEB system operates at speeds above
approximately 3 MPH (5 km/h).
If a risk of a forward collision is detected, the
FEB system will provide the first warning to
the driver by flashing the driver assist system
forward indicator (orange)
and the vehicle
ahead detection indicator (orange), and
providing an audible warning. In addition,
the FEB system pushes the accelerator
pedal up. If the driver releases the accel-
erator pedal, then the system applies partial
braking.
If the driver applies the brakes quickly and
forcefully after the warning, and the FEB
system detects that there is still the possi-
bility of a forward collision, the system will
automatically increase the braking force.
If a forward collision is imminent and the
driver does not take action, the FEB system
issues the second visual (red) and audible
warning and automatically applies harder
braking.
NOTE:
The vehicle’s stop lights come on when
braking is performed by the FEB system.
Depending on vehicle speed and distance to
the vehicle ahead, as well as driving and
roadway conditions, the system may help
the driver avoid a forward collision or may
Starting and driving5-105

5-106Starting and driving
help mitigate the consequences of a collision
should one be unavoidable.
If the driver is handling the steering wheel,
accelerating or braking, the FEB system will
function later or will not function.
The automatic braking will cease under the
following conditions:
.When the steering wheel is turned as far
as necessary to avoid a collision.
. When the accelerator pedal is depressed.
. When there is no longer a vehicle de-
tected ahead.
If the FEB system has stopped the vehicle,
the vehicle will remain at a standstill for
approximately 2 seconds before the brakes
are released.

5-128Starting and driving
You may hear a noise under the following
conditions. However, this is not a malfunc-
tion.
.When the hybrid system is started or
stopped.
. When the steering wheel is turned in the
full lock position.BRAKING PRECAUTIONS
This vehicle is equipped with two braking
systems.
. Hydraulic brake system
. Regenerative brake system
Hydraulic brake system
The brake system has two separate hydrau-
lic circuits. If one circuit malfunctions, you
will still have braking at two wheels.
Regenerative brake system
See “Regenerative brake” (P.Hybrid System-
8).
Using the brakes
Avoid resting your foot on the brake pedal
while driving. This will cause overheating of
the brakes, wearing out the brake and pads
faster and reduce 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
.While driving on a slippery surface,
be careful when braking, accelerating
or downshifting. Abrupt braking or
accelerating could cause the wheels
to skid and result in an accident.
. If the INFINITI Direct Response Hy-
brid
®System is not running or is
turned off while driving, the power
assist for the brakes will be limited.
Braking will be harder.
CAUTION
You may hear a operational noise when
the brake pedal is depressed. This is not a
malfunction.
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 brakes, drive the vehicle at a safe
speed while lightly tapping the brake pedal
BRAKE SYSTEM

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 drums/rotors are replaced, in
order to assure the best braking perfor-
mance.
This procedure is described in the vehicle
service manual. It is recommended you visit
an INFINITI retailer for this service.
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 vehicle at
all times.
ANTI-LOCK BRAKING SYSTEM
(ABS)
WARNING
.The Anti-lock Braking System (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
stopping distances on slippery sur- faces will be longer than on normal
surfaces even with ABS. Stopping
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
vehicle 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.
— For detailed information, see “Wheels and tires” (P.8-28) of
this manual.
The Anti-lock Braking System (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.
Starting and driving5-129
BRAKE ASSIST

5-130Starting and driving
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
ABS 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 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 hybrid system 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 mal-
function, 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 you visit
an INFINITI retailer for this service.
Normal operation
The ABS operates at speeds above 3 to 6
MPH (5 to 10 km/h).
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
properly. However, the pulsation may indi-
cate that road conditions are hazardous and
extra care is required while driving.
The Vehicle Dynamic Control (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 or
motor output to reduce drive wheel slip
based on vehicle speed (traction control
function).
. Controls brake pressure at individual
wheels and engine or 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 to
maintain control of the vehicle, but it cannot
prevent loss of vehicle control in all driving
situations.
When the VDC system operates, the VDC
warning light
in the instrument panel
flashes so note the following:
. The road may be slippery or the system
may determine some action is required to
VEHICLE DYNAMIC CONTROL
(VDC) SYSTEM