2018 INFINITI Q50 check engine light

5-128Starting and driving
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.5-132).

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
Starting and driving5-129

5-132Starting and driving
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
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 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 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 out-
put to reduce drive wheel slip based on
vehicle speed (traction control function).
. Controls brake pressure at individual
wheels and engine 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
help keep the vehicle on the steered path.
VEHICLE DYNAMIC CONTROL
(VDC) SYSTEM

5-138Starting and driving
NOTE:
It may take some time until the Idling Stop
System activates under the following con-
ditions:
.when the battery is discharged.
. when the outside temperature is low or
high.
. when the battery is replaced or the
battery terminal is disconnected for
extended periods and then reconnected.
NOTE:
When the Idling Stop System indicator light
illuminates, the engine starts running auto-
matically under at least one of the following
conditions:
. The brake pedal is released with the shift
lever in the D (Drive) or N (Neutral)
position.
. The shift lever is placed in the D (Drive)
or R (Reverse) position from the N
(Neutral) or P (Park) position.
. The driver’s seat belt is unfastened, or
the driver’s door is open.
. The battery voltage becomes low (due to
electrical load from other vehicle sys-
tems like headlights, heaters, etc., or
auxiliary devices connected to the 12
volt socket inside the vehicle).
. The vehicle speed is above about 1 MPH
(2 km/h). .
The front defroster is operated.
. The rear window defroster is operated.
. When the temperature inside the vehicle
is lower than approximately 68°F
(20°C).
. When the temperature inside the vehicle
is higher than approximately 86°F
(30°C). (When the air conditioner is
off, the Idling Stop System will operate.)
. When the front defroster is turned on.
(The engine may not starts depending
on the outside temperature.)
. When more than 3 minutes have elapsed
since the Idling Stop System was active.
. When the accelerator pedal is depressed.
. When the steering wheel is operated.
(The steering wheel operation may be-
come heavy, but this is not a malfunc-
tion.)
. When the battery capacity is low.
. When the power consumption is high.
. When the shift lever is placed in the R
(Reverse) position.
NOTE:
The following condition will prevent the
Idling Stop System from automatically re-
starting the engine. Starting the engine
with the ignition switch operation is then
necessary: .
The hood is open.
Use this system while waiting at stoplight,
etc. When the vehicle is stopped for long
periods of time, turn off the engine.
When the engine is stopped by the Idling
Stop System, heating, cooling and dehumi-
difying functions will be deactivated. To
avoid the air conditioning functions from
being deactivated, turn off the Idling Stop
mode by pushing the Idling Stop OFF switch.
RETROGRADE MOVEMENT
CONTROL FUNCTION
This system is designed to reduce the retro-
grade movement that occurs while the
driver’s foot changes from depressing the
brake pedal to the accelerator pedal when
moving the vehicle while the Idling Stop
System is active on a hilly road.
IDLING STOP SYSTEM DISPLAY
The status of the Idling Stop System can be
checked in the vehicle information display.

automatically stopping during the same
journey.
. Whenever the Idling Stop System is
deactivated the indicator light
on the
Idling Stop OFF switch illuminates. In
this condition the Idling Stop System
cannot prevent unnecessary fuel con-
sumption, exhaust emissions, or noise
during your journey.
. If the Idling Stop System is malfunction-
ing, the indicator light
on the Idling
Stop OFF switch illuminates.
NOTE:
The Idling Stop System ON or OFF message
is displayed for a few seconds in the vehicle
information display when the Idling Stop
OFF switch is pushed. See “Idling Stop
System ON or OFF” (P.5-139).
FREEING A FROZEN DOOR LOCK
To prevent a door lock from freezing, apply
deicer through the key hole. If the lock
becomes frozen, heat the key before insert-
ing it into the key hole or use the Intelligent
Key system.
ANTIFREEZE
In the winter when it is anticipated that the
outside temperature will drop below 32°F
(0°C), check antifreeze to assure proper
winter protection. For additional informa-
tion, see “Engine cooling system (for
VR30DDTT engine models)” (P.8-6), “En-
gine cooling system (for 2.0L turbo gasoline
engine models)” (P.8-8) or “Intercooler cool-
ing system (for VR30DDTT engine models)”
(P.8-9).
BATTERY
If the battery is not fully charged during
extremely cold weather conditions, the bat-
tery fluid may freeze and damage the
battery. To maintain maximum efficiency,
the battery should be checked regularly. For
additional information, see “Battery” (P.8-
16).
DRAINING OF COOLANT WATER
If the vehicle is to be left outside without
antifreeze, drain the cooling system, includ-
ing the engine block. Refill before operating
the vehicle. For details, see “Engine cooling
system (for VR30DDTT engine models)”
(P.8-6) or “Engine cooling system (for 2.0L
turbo gasoline engine models)” (P.8-8).
TIRE EQUIPMENT
SUMMER tires have a tread designed to
provide superior performance on dry pave-
ment. However, the performance of these
tires will be substantially reduced in snowy
and icy conditions. If you operate your
vehicle on snowy or icy roads, INFINITI
recommends the use of MUD & SNOW or
ALL SEASON tires on all four wheels. It is
recommended you consult an INFINITI re-
tailer for the tire type, size, speed rating and
availability information.
For additional traction on icy roads, studded
tires may be used. However, some U.S.
states and Canadian provinces prohibit their
use. Check local, state and provincial laws
before installing studded tires.
Skid and traction capabilities of studded
snow tires, on wet or dry surfaces, may be
poorer than that of non-studded snow tires.
Tire chains may be used. For details, see
“Tire chains” (P.8-40) of this manual.
Starting and driving5-141
COLD WEATHER DRIVING

To shut off the engine in an emergency
situation while driving, perform the follow-
ing procedure:
.Rapidly push the push-button ignition
switch 3 consecutive times in less than
1.5 seconds, or
. Push and hold the push-button ignition
switch for more than 2 seconds. If you have a flat tire, follow the instructions
in this section.
TIRE PRESSURE MONITORING
SYSTEM (TPMS)
This vehicle is equipped with the Tire
Pressure Monitoring System (TPMS). It
monitors tire pressure of all tires except the
spare. When the low tire pressure warning
light is lit and the “Tire Pressure Low - Add
Air” warning appears in the vehicle informa-
tion display, one or more of your tires is
significantly under-inflated. If the vehicle is
being driven with low tire pressure, the
TPMS will activate and warn you of it by
the low tire pressure warning light. This
system will activate only when the vehicle is
driven at speeds above 16 MPH (25 km/h).
For more details, see “Warning lights, in-
dicator lights and audible reminders” (P.2-
10) and “Tire Pressure Monitoring System
(TPMS)” (P.5-5).
WARNING
.
Radio waves could adversely affect
electric medical equipment. Those
who use a pacemaker should contact
the electric medical equipment man-
ufacturer for the possible influences
before use. .
If the low tire pressure warning light
illuminates while driving, avoid sud-
den steering maneuvers or abrupt
braking, reduce vehicle speed, pull
off the road to a safe location and
stop the vehicle as soon as possible.
Driving with under-inflated tires may
permanently damage the tires and
increase the likelihood of tire failure.
Serious vehicle damage could occur
and may lead to an accident and
could result in serious personal injury.
Check the tire pressure for all four
tires. Adjust the tire pressure to the
recommended COLD tire pressure
shown on the Tire and Loading
Information label to turn the low tire
pressure warning light OFF. If the
light still illuminates while driving
after adjusting the tire pressure, a
tire may be flat. If you have a flat tire,
replace it with a spare tire (if so
equipped).
. Since the spare tire is not equipped
with the TPMS, when a spare tire is
mounted or a wheel is replaced, the
TPMS will not function and the low
tire pressure warning light will flash
for approximately 1 minute. The light
will remain on after 1 minute. Have
your tires replaced and/or TPMS
system reset as soon as possible. It
In case of emergency6-3
EMERGENCY ENGINE SHUT OFF FLAT TIRE

8 Do-it-yourself
Maintenance precautions ................................................ 8-3
Engine compartment check locations .......................... 8-4VR30DDTT engine....................................................... 8-4
2.0L turbo gasoline engine........................................ 8-5
Engine cooling system (for VR30DDTT
engine models).................................................................... 8-6
Checking engine coolant level ................................. 8-7
Changing engine coolant............................................ 8-7
Engine cooling system (for 2.0L turbo gasoline
engine models).................................................................... 8-8
Checking engine coolant level................................... 8-8
Changing engine coolant............................................ 8-9
Intercooler cooling system (for VR30DDTT
engine models).................................................................... 8-9 Checking intercooler coolant level........................ 8-10
Changing intercooler coolant................................. 8-10
Engine oil.....................................................................\
...... 8-10 Checking engine oil level .......................................... 8-11
Changing engine oil and filter................................. 8-11
Automatic Transmission Fluid (ATF).......................... 8-13
Power steering fluid (models with hydraulic pump
electric power steering).................................................. 8-14
Brake fluid...................................................................\
....... 8-14
Window washer fluid...................................................... 8-15 Battery........................................................................\
........ 8-16
Main battery location.............................................. 8-16
Auxiliary battery location (for 2.0L turbo
gasoline engine models).......................................... 8-17
Checking battery fluid level................................... 8-17
Jump starting............................................................. 8-18
Variable voltage control system ................................. 8-19
Drive belts ........................................................................\
. 8-19
Spark plugs....................................................................... 8-20 Replacing spark plugs............................................. 8-20
Air cleaner........................................................................\
.. 8-21
Windshield wiper blades ............................................... 8-21 Cleaning....................................................................... 8-21
Replacing..................................................................... 8-22
Brakes..................................................................\
............... 8-22 Self-adjusting brakes............................................... 8-22
Brake pad wear warning........................................ 8-22
Fuses...................................................................\
................ 8-23 Engine compartment.............................................. 8-24
Passenger compartment ........................................ 8-25
Intelligent Key battery replacement........................... 8-26
Lights........................................................................\
......... 8-28 Headlights................................................................... 8-29
Exterior and interior lights..................................... 8-29

8-12Do-it-yourself
JVM0667X
2.0L turbo gasoline engine
JVM0428X
2.0L turbo gasoline engine
Engine oil and filter
1. Place a large drain pan under the drainplug.
2. Remove the oil filler cap.
3. Remove the drain plug
with a wrench
and completely drain the oil.
CAUTION
Be careful not to burn yourself, as the
engine oil is hot.
.Waste oil must be disposed of prop-
erly.
.Check your local regulations.
4. (Perform steps 4 to 7 only when the engine oil filter change is needed.)
Loosen the oil filter
with an oil filter
wrench. Remove the oil filter by turning it
by hand.
5. Wipe the engine oil filter mounting sur- face with a clean rag.
CAUTION
Be sure to remove any old rubber gasket
remaining on the mounting surface of
the engine. Failure to do so could lead to engine damage.
6. Coat the gasket on the new filter with clean engine oil.
7. For VR30DDTT engine models: Screw in the oil filter clockwise until a slight
resistance is felt, then tighten addition-
ally more than 2/3 turn.
For 2.0L turbo gasoline engine models:
Securely tighten the oil filter. Do not use
excessive force.
Oil filter tightening torque:
VR30DDTT engine models
11 to 15 ft-lb
(14.7 to 20.6 N·m)
2.0L turbo gasoline engine models 19 ft-lb
(25 N·m)
8. Clean and re-install the drain plug with a new washer. Securely tighten the drain
plug with a wrench.
Drain plug tightening torque:
VR30DDTT engine models22 to 29 ft-lb
(29.4 to 39.2 N·m)
2.0L turbo gasoline engine models 22 ft-lb
(30 N·m)