2018 INFINITI Q50 HYBRID Owner's Manual

wheel, may reduce the steering per-
formance.
Direct Adaptive Steering is designed to
control the steering force and steering angle
according to the vehicle speed and amount
of turning of the steering wheel.
The steering characteristic can be selected
using the INFINITI Drive Mode Selector. See
“INFINITI Drive Mode Selector” (P.5-21).
If the VDC system is turned off, the setting
of steering becomes Standard mode.
If the power steering warning light illumi-
nates while the hybrid system is running, it
may indicate that Direct Adaptive Steering is
not functioning properly and may need
servicing. It is recommended you have the
system checked by an INFINITI retailer. (See
“Power steering warning light” (P.2-14).)
When the power steering warning light
illuminates with the hybrid system running,
the power assist for the steering will cease
operation. You will still have control of the
vehicle. However, greater steering effort will
be needed, especially in sharp turns and at
low speeds.
If Direct Adaptive Steering is malfunction-
ing, the steering wheel may turn slightly even
when driving on a straight road.
Under the following conditions, the steering wheel may turn slightly even when driving on
a straight road. This is due to a protection
mechanism for Direct Adaptive Steering. The
steering wheel will return to the normal
position after the protection mechanism is
deactivated.
Condition A
.
When the engine is stalled or likely to be
stalled
. When the steering wheel is held in the full
lock position or when the front tire
touches an obstruction.
. When the battery is discharged
To return the steering wheel to the normal
position, stop the vehicle in a safe location
and stop operating the steering wheel. Then
drive the vehicle for a short period of time.
Condition B
. When the steering wheel is operated
repeatedly or continuously while parking
or driving at a very low speed. In this
case, the power assist for the steering
wheel will be reduced.
To return the steering wheel to the normal
position, stop the vehicle in a safe location
and wait for a period of time, without
operating the steering wheel, until the
temperature of Direct Adaptive Steering
cools down. Avoid repeated steering wheel
operations that could cause Direct Adaptive
Steering to overheat. When the vehicle is tested on the 2-wheel
dynamometer, the power steering warning
light may illuminate. To turn off the power
steering warning light, stop the vehicle in a
safe location, turn the hybrid system off,
restart the hybrid system, and then drive the
vehicle for a period of time.
The following conditions do not indicate a
malfunction of Direct Adaptive Steering.
.
You may notice wider steering play when
the ignition switch is in the OFF or ACC
position compared to when it is in the
ON position.
. After the hybrid system is started, the
steering wheel may turn slightly even
when driving on a straight road. To
return to the normal position, drive the
vehicle on a straight road for a period of
time.
. After the hybrid system is started, the
steering wheel may move if the steering
wheel was turned to the fully locked
position while the ignition switch was in
the OFF position.
. After the vehicle is tested on the 4-wheel
dynamometer, the steering wheel may
turn slightly even when driving on a
straight road. To return the steering
wheel to the normal position, drive the
vehicle on a straight road for a period of
time.
Starting and driving5-127

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

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.
See “Vehicle Dynamic Control (VDC) warn-
ing light” (P.2-15).
If a malfunction occurs in the system, the
VDC warning light
illuminates in the
instrument panel. The VDC system automa-
tically turns off.
The VDC OFF switch is used to turn off the
VDC system. The VDC off indicator light
illuminates to indicate 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 VDC warning light
flashes if
this occurs. All other VDC functions are off,
except for rise-up and build-up, and brake
force distribution, and the VDC warning
light
will not flash. The VDC system is
automatically reset to on when the ignition
switch is placed in the off position then back
to the on position.
See “Vehicle Dynamic Control (VDC) warn-
ing light” (P.2-15) and “Vehicle Dynamic Control (VDC) off indicator light” (P.2-17).
The computer has a built-in diagnostic
feature that tests the system each time you
start the INFINITI Direct Response Hybrid
®
System and move the vehicle forward or in
reverse at a slow speed. 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 indication of a mal-
function.
RISE-UP AND BUILD-UP
The system gradually adjusts braking power
during normal braking to help provide an
enhanced brake feel.
BRAKE FORCE DISTRIBUTION
During braking while driving through turns,
the system optimizes the distribution of
force to each of the four wheels depending
on the radius of the turn.
WARNING
.
The VDC system is designed to help
the driver maintain stability but does
not prevent accidents due to abrupt
steering operation at high speeds or
by careless or dangerous driving
techniques. Reduce vehicle speed
and be especially careful when driving and cornering on slippery surfaces
and always drive carefully.
. The rise-up and build-up, and brake
force distribution system may not be
effective depending on the driving
condition. Always drive carefully and
attentively.
. Do not modify the vehicle’s suspen-
sion. If suspension parts such as
shock absorbers, struts, springs, sta-
bilizer bars, bushings and wheels are
not INFINITI recommended for your
vehicle or are extremely deteriorated,
the VDC system may not operate
properly. This could adversely affect
vehicle handling performance, and
the VDC warning light
may
illuminate.
. If brake related parts such as brake
pads, rotors and calipers are not
INFINITI recommended or are extre-
mely deteriorated, the VDC system
may not operate properly and the
VDC warning light
may illumi-
nate.
. If engine control related parts are not
INFINITI recommended or are extre-
mely deteriorated, the VDC warning
light
may illuminate.
. When driving on extremely inclined
surfaces such as higher banked cor-
Starting and driving5-131

5-132Starting and driving
ners, the VDC system may not oper-
ate properly and the VDC warning
light
may illuminate. Do not drive
on these types of roads.
. When driving on an unstable surface
such as a turntable, ferry, elevator or
ramp, the VDC warning light
may
illuminate. This is not a malfunction.
Restart the hybrid system after driv-
ing onto a stable surface.
. If wheels or tires other than the
INFINITI recommended ones are
used, the VDC system may not oper-
ate properly and the VDC warning
light
may illuminate.
. The VDC system is not a substitute
for winter tires or tire chains on a
snow covered road. This system senses driving based on the
driver’s steering and acceleration/braking
patterns, and controls brake pressure at
individual wheels to help smooth vehicle
response.
When the SPORT mode is selected by the
INFINITI Drive Mode Selector, the amount
of brake control provided by the active trace
control is reduced.
When the PERSONAL mode is selected, the
active trace control can be set to ON
(enabled) or OFF (disabled). See “INFINITI
Drive Mode Selector” (P.5-21).
When the VDC OFF switch is used to turn
off the VDC system, the active trace control
is also turned off.
ACTIVE TRACE CONTROL

JVS0249X
When the active trace control is operated
and the “Chassis Control” mode is selected in
the trip computer, the active trace control
graphics are shown in the vehicle informa-
tion display. (See “Trip computer” (P.2-27).)
If the chassis control warning message
appears in the vehicle information display,
it may indicate that the active trace control
is not functioning properly. It is recom-
mended you have the system checked by
an INFINITI retailer. (See “31. Chassis con-
trol warning” (P.2-23).)
WARNING
The active trace control may not be
effective depending on the driving con-
dition. Always drive carefully and atten-
tively.
When the active trace control is operating,
you may feel a pulsation in the brake pedal
and hear a noise. This is normal and indicates
that the active trace control is operating
properly.
Even if the active trace control is set to OFF,
some functions will remain on to assist the driver (for example, avoidance scenes).
Starting and driving5-133

5-134Starting and driving
WARNING
.Never rely solely on the hill start
assist system to prevent the vehicle
from moving backward on a hill.
Always drive carefully and atten-
tively. 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
designed to hold the vehicle at a
standstill 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 system may not
prevent the vehicle from rolling back-
wards 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. 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.
The hill start assist system will operate
automatically under the following condi-
tions:
.
The transmission is shifted to a forward
or reverse gear.
. The vehicle is stopped completely on a hill
by applying the brake.
The maximum holding 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 transmission is shifted to the N
(Neutral) or P (Park) position or on a flat and
level road.
The chassis control is an electric control
module that includes the following func-
tions:
. Log-in function (See “Log-in function”
(P.3-15).)
. INFINITI Drive Mode Selector (See
“INFINITI Drive Mode Selector” (P.5-
21).)
. Active Lane Control (if so equipped) (See
“Active Lane Control” (P.5-24).)
. Active Trace Control (See “Active trace
control” (P.5-132).)
HILL START ASSIST SYSTEM CHASSIS CONTROL