Engine control INFINITI Q50 2019 Workshop Manual

5-72Starting and driving
sired operation.
Frequency of operation: 24.05GHz —
24.25GHz
Field Strength: Not greater than 2.5V/m
peak (0.25V/m average) at a distance of 3
mPRECAUTIONS ON CRUISE
CONTROL
.If the cruise control system malfunctions,
it will cancel automatically. The cruise
indicator (green) in the vehicle informa-
tion display will then blink to warn the
driver.
. If the engine coolant temperature be-
comes excessively high, the cruise con-
trol system will be canceled
automatically.
. If the cruise indicator (green) blinks, turn
the cruise control MAIN switch off and
have the system checked. It is recom-
mended you visit an INFINITI retailer for
this service.
. The cruise indicator (green) may some-
times blink when the cruise control MAIN
switch is turned ON while pushing the
SET/COAST (-), RESUME/ACCELER-
ATE (+) or CANCEL switch. To properly
set the cruise control system, perform
the steps below in the order indicated.
WARNING
Do not use the cruise control when
driving under the following conditions:
. when it is not possible to keep the
vehicle at a set speed .
in heavy traffic or in traffic that
varies in speed
. on winding or hilly roads
. on slippery roads (rain, snow, ice,
etc.)
. in very windy areas
Doing so could cause a loss of vehicle
control and result in an accident.
CRUISE CONTROL (if so equipped)

5-94Starting and driving
3. Push, then quickly release the SET/COAST (-) switch. Each time you do this,
the set speed will decrease by about 1
MPH (1.6 km/h).
To resume the preset speed, push and
release the RESUME/ACCELERATE (+)
switch. The vehicle will resume the last set
cruising speed when the vehicle speed is over
25 MPH (40 km/h).
System temporarily unavailable
A chime sounds under the following condi-
tions and the control is automatically can-
celed.
. When the vehicle slows down more than
8 MPH (13 km/h) below the set speed
. When the shift lever is not in the D (Drive)
or manual shift mode
. When the parking brake is applied.
. When the VDC operates (including the
traction control system)
. When a wheel slips
JVS0306X
Warning
When the system is not operating properly,
the chime sounds and the color of the cruise
indicator will change to orange.
Action to take:
If the color of the cruise indicator changes to
orange, stop the vehicle in a safe place and
place the shift lever in the P (Park) position.
Turn the engine off, restart the engine,
resume driving and then perform the setting
again.
If it is not possible to set or the indicator
stays on, it may indicate that the system is
malfunctioning. Although the vehicle is still
driveable under normal conditions, have the vehicle checked. It is recommended you visit
an INFINITI retailer for this service.

5-100Starting and driving
JVS0845X
Dynamic driver assistance switch
Driver assist system forward indicator
(green) (on the vehicle information dis-
play)
Lower display
TURNING THE DCA SYSTEM ON/
OFF
To turn on the DCA system, push the
dynamic driver assistance switchon the
steering wheel after starting the engine. The
driver assistance switch indicator
in the
vehicle information display will appear. Push
the dynamic driver assistance switch
again
to turn off the DCA system. The driver
assistance switch indicator
will turn off.
The system will start to operate after the
vehicle speed is above approximately 3 MPH
(5 km/h).
The dynamic driver assistance switch
is
used for the DCA, Active Lane Control (if so
equipped), LDP and BSI systems. When the
dynamic driver assistance switch
is
pushed, Active Lane Control, LDP and BSI
systems will also turn on or off simulta-
neously. The DCA system can be individually
set to on or off on the lower display
. If the
system is set to off, the system will not turn
on even if the dynamic driver assistance
switch
is pushed to on. To set the system
to on or off on the display, see “How to
enable/disable the DCA system” (P.5-101).
When the conventional (fixed speed) cruise
control mode is operating, the DCA system
will not operate. (To use the DCA system,
turn the conventional (fixed speed) cruise
control mode off, then push the dynamic

driver assistance switch.)
For details about the conventional (fixed
speed) cruise control mode, see “Intelligent
Cruise Control (ICC)” (P.5-74).
When the engine is turned off, the DCA
system is automatically turned off.
JVS0246X
HOW TO ENABLE/DISABLE THE
DCA SYSTEM
Perform the following steps to enable or
disable the DCA system.
1. Push the MENU
button and touch
[Driver Assistance] on the lower display.
2. Touch [Forward Assist].
3. Touch [Distance Control Assist] to en- able or disable the system.
JVS0225X
DCA SYSTEM DISPLAY AND IN-
DICATORS
The display is located between the speed-
ometer and tachometer.
1. Driver assist system forward indicator
.Driver assist system forward indicator(green):
Indicates that the DCA system is ON.
.Driver assist system forward indicator(orange):
Indicates whether there is a malfunc-
tion in the DCA system.
2. Vehicle ahead detection indicator: Indicates whether it detects a vehicle in
Starting and driving5-101

For details about the VDC system, see
“Vehicle Dynamic Control (VDC) system”
(P.5-133)
. When the VDC or ABS (including the
traction control system) operates
. When the INFINITI Drive Mode Selector
is turned to the SNOW mode (To use the
DCA system, turn the INFINITI Drive
Mode Selector to a mode other than the
SNOW mode, then turn on the dynamic
driver assistance switch
.) For details
about the INFINITI Drive Mode Selector,
see “INFINITI Drive Mode Selector” (P.5-
22)
. When the radar signal is temporarily
interrupted
Action to take:
When the conditions listed above are no
longer present, turn the DCA system back on
to use the system.
Condition B
Under the following conditions, making it
impossible to detect a vehicle ahead, the
DCA system is automatically canceled.
The chime will sound, the driver assist
system forward indicator (orange) and the
“front radar obstruction” warning message
will appear in the vehicle information display.
. When the radar sensor area of the front bumper is covered with dirt or is ob-
structed
Action to take:
If the driver assist system forward indicator
(orange) and the warning message appear,
stop the vehicle in a safe place, place the
shift lever in the P (Park) position and turn
the engine off. When the radar signal is
temporarily interrupted, clean the sensor
area of the front bumper and restart the
engine. If the warning message continues to
be displayed, have the DCA system checked.
It is recommended you visit an INFINITI
retailer for this service.
. When driving on roads with limited road
structures or buildings (for example, long
bridges, deserts, snow fields, driving next
to long walls)
Action to take:
When the above conditions no longer exist,
the DCA system will resume automatically.SYSTEM MALFUNCTION
When the DCA system is not operating
properly, the chime sounds, the driver assist
system forward indicator (orange) and the
system “malfunction” warning message will
appear in the vehicle information display. Action to take:
If the driver assist system forward indicator
(orange) and the warning message appear,
stop the vehicle in a safe place and place the
shift lever in the P (Park) position. Turn the
engine off, restart the engine, and turn on
the DCA system again.
If it is not possible to set the system or the
indicator stays on, it may indicate that the
system is malfunctioning. Although the
vehicle is still driveable under normal con-
ditions, have the vehicle checked. It is
recommended you visit an INFINITI retailer
for this service.
SYSTEM MAINTENANCE
The sensor for the DCA system is common
with the Intelligent Cruise Control (ICC)
system and is located behind the lower grille
of the front bumper.
For the sensor maintenance, see “Intelligent
Cruise Control (ICC)” (P.5-74).
FCC Notice:
For USA:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1.
This device may not cause harmful
interference, and
Starting and driving5-105

5-124Starting and driving
4. Drive at economical speeds and dis-tances.
.Observing the speed limit and notexceeding 60 MPH (97 km/h) (where
legally allowed) can improve fuel
efficiency due to reduced aerody-
namic drag.
.Maintaining a safe following distance
behind other vehicles reduces unne-
cessary braking.
.Safely monitoring traffic to anticipatechanges in speed permits reduced
braking and smooth acceleration
changes.
.Select a gear range suitable to roadconditions.
5. Use cruise control.
.Using cruise control during highway driving helps maintain a steady speed.
.Cruise control is particularly effectivein providing fuel savings when driving
on flat terrains.
6. Plan for the shortest route.
.Utilize a map or navigation system to determine the best route to save time.
7. Avoid idling.
.Shutting off your engine when safe for stops exceeding 30-60 seconds
saves fuel and reduces emissions. 8. Buy an automated pass for toll roads.
.Automated passes permit drivers to
use special lanes to maintain cruising
speed through the toll and avoid
stopping and starting.
9. Winter warm up.
.Limit idling time to minimize impact to fuel economy.
.Vehicles typically need no more than30 seconds of idling at start-up to
effectively circulate the engine oil
before driving.
.Your vehicle will reach its ideal oper-ating temperature more quickly while
driving versus idling.
10. Keeping your vehicle cool.
.Park your vehicle in a covered parking area or in the shade whenever possi-
ble.
.When entering a hot vehicle, openingthe windows will help to reduce the
inside temperature faster, resulting in
reduced demand on your A/C system. .
Keep your engine tuned up.
. Follow the recommended scheduled
maintenance.
. Keep the tires inflated to the correct
pressure. Low tire pressure increases tire
wear and lowers fuel economy.
. Keep the wheels in correct alignment.
Improper alignment increases tire wear
and lowers fuel economy.
. Use the recommended viscosity engine
oil. (See “Engine oil and oil filter recom-
mendation” (P.10-8).)
INCREASING FUEL ECONOMY

5-128Starting and driving
moves.
4. Push the ignition switch to the OFF position.ELECTRIC POWER STEERING
TYPE
WARNING
.If the engine is not running or is
turned off while driving, the power
assist for the steering will not work.
Steering will be harder to operate.
. When the power steering warning
light illuminates with the engine run-
ning, the power assist for the steer-
ing will cease operation. You will still
have control of the vehicle but the
steering will be harder to operate.
The electric power steering is designed to
provide power assist while driving to oper-
ate the steering wheel with light force.
When the steering wheel is operated re-
peatedly or continuously while parking or
driving at a very low speed, the power assist
for the steering wheel will be reduced. This is
to prevent overheating of the electric power
steering and protect it from getting da-
maged. While the power assist is reduced,
steering wheel operation will become heavy.
When the temperature of the electric power
steering goes down, the power assist level
will return to normal. Avoid repeating such steering wheel operations that could cause
the electric power steering to overheat.
You may hear a sound when the steering
wheel is operated quickly. However, this is
not a malfunction.
If the power steering warning light illumi-
nates while the engine is running, it may
indicate the electric power steering is not
functioning properly and may need servicing.
It is recommended you have the electric
power steering checked by an INFINITI
retailer. (See “Power steering warning light”
(P.2-14).)
When the power steering warning light
illuminates with the engine running, the
power assist for the steering will cease
operation. You will still have control of the
vehicle. However, greater steering effort is
needed, especially in sharp turns and at low
speeds.
HYDRAULIC PUMP ELECTRIC
POWER STEERING TYPE
WARNING
When the power steering warning light
illuminates with the engine running, the
power assist for the steering will cease
operation. You will still have control of
POWER STEERING

the vehicle, but the steering will be much
harder to operate.
The hydraulic pump electric power steering
is designed to provide power assistance
while driving to operate the steering wheel
with light force.
When the steering wheel is operated re-
peatedly or continuously while parking or
driving at a very low speed, the power assist
for the steering wheel will be reduced. This is
to prevent overheating of the hydraulic
pump electric power steering and protect it
from getting damaged. While the power
assist is reduced, steering wheel operation
will become heavy. If the steering wheel
operation is still performed, the power
steering may stop and the power steering
warning light will illuminate. Stop the engine
and place the ignition switch in the OFF
position. The temperature of the hydraulic
pump electric power steering will go down
and the power assist level will return to
normal after starting the engine. The power
steering warning light will go off. Avoid
repeating such steering wheel operations
that could cause the hydraulic pump electric
power steering to overheat.
You may hear a noise from the front of the
vehicle when the steering wheel is operated.
This is not a malfunction. If the power steering warning light illumi-
nates while the engine is running, it may
indicate the hydraulic pump electric power
steering is not functioning properly and may
need servicing. It is recommended you have
the hydraulic pump electric power steering
checked by an INFINITI retailer.
When the power steering warning light
illuminates with the engine running, the
power assist for the steering will cease
operation but you will still have control of
the vehicle. At this time, greater steering
efforts are required to operate the steering
wheel, especially in sharp turns and at low
speeds.
DIRECT ADAPTIVE STEERING
TYPE
WARNING
.
When the power steering warning
light illuminates with the engine run-
ning, the power assist for the steer-
ing will cease operation. You will still
have control of the vehicle, but the
steering will be harder to operate.
. If wheels or tires other than the
INFINITI recommended ones are
used, Direct Adaptive Steering may
not operate properly and the power steering warning light may illumi-
nate.
. 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,
Direct Adaptive Steering may not
operate properly and the power
steering warning light may illumi-
nate.
. Do not modify the vehicle’s steering.
If steering parts are not INFINITI
recommended for your vehicle or are
extremely deteriorated, Direct Adap-
tive Steering may not operate prop-
erly and the power steering warning
light may illuminate.
. If the VDC warning light illuminates,
the power steering warning light may
also illuminate at the same time. Stop
the vehicle in a safe location, turn the
engine off and restart the engine. If
the power steering warning light
continues to illuminate, have the
system checked. It is recommended
you visit an INFINITI retailer for this
service. For VDC system, see “Vehicle
Dynamic Control (VDC) system”
(P.5-133).
Starting and driving5-129

5-130Starting and driving
CAUTION
.Do not place the ignition switch is in
the ON position while the steering
wheel or a tire is removed.
. Do not turn the steering wheel as
much as possible while the ignition
switch is in any position other than
the ON position.
. Installing an accessory on the steer-
ing wheel, or changing the steering
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.5-22).
If the VDC system is turned off, the setting
of steering becomes standard mode.
If the power steering warning light illumi-
nates while the engine 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 engine 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 engine off, restart the
engine, 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 engine 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 engine 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.
You may hear a noise under the following
conditions. However, this is not a malfunc-
tion.
. When the engine is started or stopped.
. When the steering wheel is turned in the
full lock position.BRAKING PRECAUTIONS
The brake system has two separate hydrau-
lic circuits. If one circuit malfunctions, you
will still have braking at two wheels.
Vacuum assisted brakes
The brake booster aids braking by using
engine 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
vehicle and the stopping distance will be
longer.
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 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 brakes, drive the vehicle at a safe
speed while lightly tapping 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 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
Starting and driving5-131
BRAKE SYSTEM