ignition INFINITI Q50 2021 Owners Manual

JUMP STARTING
If jump starting is necessary, see “Jump
starting” (P.6-5). If the engine does not start
by jump starting, the battery may have to be
replaced. It is recommended you visit an
INFINITI retailer for this service.CAUTION
.Do not ground accessories directly to
the battery terminal. Doing so will
bypass the variable voltage control
system and the vehicle battery may
not charge completely.
. Use electrical accessories with the
engine running to avoid discharging
the vehicle battery.
The variable voltage control system mea-
sures the amount of electrical discharge
from the battery and controls voltage gen-
erated by the generator.
JVM0655X
1. Water pump
2. Alternator
3. Drive belt auto-tensioner
4. Crankshaft pulley
5. Air conditioner compressor
WARNING
Be sure the ignition switch is in the OFF
or LOCK position before servicing drive
belts. The engine could rotate unexpect-
edly.
1. Visually inspect each belt for signs of unusual wear, cuts, fraying or looseness.
Do-it-yourself8-13
VARIABLE VOLTAGE CONTROL SYSTEMDRIVE BELTS

8-14Do-it-yourself
If the belt is in poor condition or loose,
have it replaced or adjusted. It is recom-
mended you visit an INFINITI retailer for
this service.
2. Have the belts checked regularly for condition and tension in accordance with
the maintenance schedule shown in the
“9. Maintenance and schedules” section.
WARNING
Be sure the engine and the ignition
switch are off and that the parking
brake is engaged securely.
CAUTION
Be sure to use the correct socket to
remove the spark plugs. An incorrect
socket can damage the spark plugs.
SDI2020
REPLACING SPARK PLUGS
If replacement is required, it is recommended
you visit an INFINITI retailer for this service.
Iridium-tipped spark plugs
It is not necessary to replace the iridium-
tipped spark plugs as frequently as the
conventional type spark plugs since they will
last much longer. Follow the maintenance
schedule shown in the “9. Maintenance and
schedules” section, but do not reuse them by
cleaning or regapping.
Always replace spark plugs with recom-
mended or equivalent ones.
SPARK PLUGS

Under some driving or climate conditions,
occasional brake squeak, squeal or other
noise may be heard. Occasional brake noise
during light to moderate stops is normal and
does not affect the function or performance
of the brake system.
Proper brake inspection intervals should be
followed.For additional information, see the
maintenance schedule shown in the “9.
Maintenance and schedules” section.
JVM0255X
JVM0734X
ENGINE COMPARTMENT
WARNING
Never use a fuse of a higher or lower
amperage rating than that specified on
the fuse box cover. This could damage
the electrical system or electronic con-
trol units or cause a fire.
If any electrical equipment does not operate,
check for an open fuse.
1. Be sure the ignition switch is placed in the OFF or LOCK position and the
headlight switch is turned to OFF.
2. Open the engine hood.
3. Remove the fuse/fusible link holder cover.
4. Remove the fuse with the fuse puller.
Do-it-yourself8-17
FUSES

8-18Do-it-yourself
SDI1754
5. If the fuse is open, replace it with a
new fuse. Spare fuses are stored in the
passenger compartment fuse box.
6. If a new fuse also opens, have the electrical system checked and repaired.
It is recommended you visit an INFINITI
retailer for this service.
Fusible links
If any electrical equipment does not operate
and fuses are in good condition, check the
fusible links. If any of these fusible links are
melted, replace only with genuine INFINITI
parts.
JVM0256X
PASSENGER COMPARTMENT
WARNING
Never use a fuse of a higher or lower
amperage rating than that specified on
the fuse box cover. This could damage
the electrical system or electronic con-
trol units or cause a fire.
If any electrical equipment does not operate,
check for an open fuse.
1. Be sure the ignition switch is placed in the OFF or LOCK position and the
headlight switch is turned to OFF. 2. Open the fuse box lid.
3. Remove the fuse with the fuse puller
.
4. If the fuse is open, replace it with a new fuse.
5. If a new fuse also opens, have the electrical system checked and repaired.
It is recommended you visit an INFINITI
retailer for this service. Spare fuses are
stored in the fuse box.

JVM0257X
Extended storage fuse switch (if so
equipped)
To reduce battery drain, the extended
storage fuse switch comes from the factory
switched off. Prior to delivery of your
vehicle, the switch is pushed in (switched
on) and should always remain on.
If the extended storage fuse switch is not
pushed in (switched on), the “Shipping Mode
On, Push Storage Fuse” warning may appear
in the vehicle information display. See “19.
Extended storage fuse warning” (P.2-22).
If any electrical equipment does not operate,
remove the extended storage fuse switch
and check for an open fuse.NOTE:
If the extended storage fuse switch mal-
functions or if the fuse is open, it is not
necessary to replace the switch. In this case,
remove the extended storage fuse switch
and replace it with a new fuse of the same
rating.
How to remove the extended storage fuse
switch:
1. To remove the extended storage fuse switch, be sure the ignition switch is in
the OFF or LOCK position.
2. Be sure the headlight switch is in the OFF position.
3. Remove the fuse box cover.
4. Pinch the locking tabs
found on each
side of the storage fuse switch.
5. Pull the storage fuse switch straight out from the fuse box
.
CAUTION
Be careful not to allow children to
swallow the battery and removed parts.
Do-it-yourself8-19
INTELLIGENT KEY BATTERY
REPLACEMENT

8-34Do-it-yourself
the tire chain must be secured or removed to
prevent the possibility of whipping action
damage to the fenders or underbody. If
possible, avoid fully loading your vehicle
when using tire chains. In addition, drive at
a reduced speed. Otherwise, your vehicle
may be damaged and/or vehicle handling
and performance may be adversely affected.
Tire chains must be installed only on the
rear wheels and not on the front wheels.
Never install tire chains on a TEMPORARY
USE ONLY spare tire (if so equipped). Never
install tire chains on a punctured run-flat tire
(if so equipped), as this could damage your
vehicle.
Do not use tire chains on dry roads. Driving
with tire chains in such conditions can cause
damage to the various mechanisms of the
vehicle due to some overstress.
SDI1662
CHANGING WHEELS AND TIRES
Tire rotation (models equipped with
same size tires on all wheels)
INFINITI recommends rotating the
tires at the specified interval shown
in the maintenance schedule. (See the
“9. Maintenance and schedules” sec-
tion. For tire replacing procedure, see
“Jacking up the vehicle and replacing
tires” (P.8-37).)
As soon as possible, tighten the
wheel nuts to the specified torque
with a torque wrench.Wheel nut tightening torque:
80 ft-lb (108 N·m)
The wheel nuts must be kept tigh-
tened to the specification at all times.
It is recommended that wheel nuts be
tightened to the specification at each
tire rotation interval.
WARNING
. After rotating the tires, check
and adjust the tire pressure.
. Do not include the T-type spare
tire or any other small size
spare tire in the tire rotation.
. For additional information re-
garding tires, refer to “Impor-
tant Tire Safety Information”
(US) or “Tire Safety Informa-
tion” (Canada) in the Warranty
Information Booklet.
After the ignition switch is placed in
the ON position, it may take a period
of time for the tire pressure to be
displayed in the vehicle information

display while the vehicle is driven.
Depending on the radio wave circum-
stance, tire pressure may not cor-
rectly be displayed.
Tire rotation (models equipped with
different size tires on front and rear)
Tires cannot be rotated on this vehi-
cle, as front tires are a different size
from rear tires.
A pin is on the front brake rotor to
prevent the rear wheels from being
installed in place of the front wheels.
The spare tire can be installed in place
of the front and rear wheels. When
installing the spare tire in the front
wheel, the hole in the spare tire wheel
must be aligned with the pin on the
brake rotor.
WARNING
.If your vehicle is equipped with
different size front and rear
tires, never install the rear
tire/wheel on the front of the
vehicle. Doing so can damage the vehicle or tire. Damage to
the tire may result in a sudden
loss of air pressure which may
cause loss of vehicle control in
some driving conditions and
cause a collision and personal
injury.
. For additional information re-
garding tires, refer to “Impor-
tant Tire Safety Information”
(US) or “Tire Safety Informa-
tion” (Canada) in the Warranty
Information Booklet.
After the ignition switch is placed in
the ON position, it may take a period
of time for the tire pressure to be
displayed in the vehicle information
display while the vehicle is driven.
Depending on the radio wave circum-
stance, tire pressure may not cor-
rectly be displayed.
SDI1663
: Wear indicator
: Wear indicator location mark. The
locations are shown by “”, “TWI”,
etc. depending on tire types.
Tire wear and damage
WARNING
. Tires should be periodically in-
spected for wear, cracking, bul-
ging or objects caught in the
tread. If excessive wear, cracks,
bulging or deep cuts are found,
the tire(s) should be replaced.
Do-it-yourself8-35

8-36Do-it-yourself
.The original tires have built-in
tread wear indicators. When
wear indicators are visible, the
tire(s) should be replaced.
. Tires degrade with age and use.
Have tires, including the spare,
over 6 years old checked by a
qualified technician, because
some tire damage may not be
obvious. Replace the tires as
necessary to prevent tire failure
and possible personal injury.
. Improper service of the spare
tire may result in serious perso-
nal injury. If it is necessary to
repair the spare tire, it is re-
commended you visit an
INFINITI retailer for this ser-
vice.
. For additional information re-
garding tires, refer to “Impor-
tant Tire Safety Information”
(US) or “Tire Safety Informa-
tion” (Canada) in the Warranty
Information Booklet.Replacing wheels and tires
When replacing a tire, use the same size,
tread design, speed rating and load carrying
capacity as originally equipped. (See “Speci-
fications” (P.10-8) for recommended types
and sizes of tires and wheels.)
After the ignition switch is placed in the ON
position, it may take a period of time for the
tire pressure to be displayed in the vehicle
information display while the vehicle is
driven. Depending on the radio wave circum-
stance, tire pressure may not correctly be
displayed.
WARNING
. The use of tires other than those
recommended or the mixed use of
tires of different brands, construc-
tion (bias, bias-belted, radial or run-
flat), or tread patterns can adversely
affect the ride, braking, handling,
ground clearance, body-to-tire clear-
ance, tire chain clearance, speed-
ometer calibration, headlight aim
and bumper height. Some of these
effects may lead to accidents and
could result in serious personal injury.
. For Two-Wheel Drive (2WD) models,
if your vehicle was originally equipped with 4 tires that were the
same size and you are only replacing
2 of the 4 tires, install the new tires
on the rear axle. Placing new tires on
the front axle may cause loss of
vehicle control in some driving condi-
tions and cause an accident and
personal injury.
. If the wheels are changed for any
reason, always replace with wheels
which have the same off-set dimen-
sion. Wheels of a different off-set
could cause premature tire wear,
degrade vehicle handling character-
istics and/or interference with the
brake discs/drums. Such interference
can lead to decreased braking effi-
ciency and/or early brake pad/shoe
wear. See “Wheels and tires” (P.10-
9) of this manual for wheel off-set
dimensions.
. 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
is recommended you visit an INFINITI
retailer for these services.

your service station manager.
If you use oxygenate-blend gasoline, please
take the following precautions as the usage
of such fuels may cause vehicle performance
problems and/or fuel system damage.
.The fuel should be unleaded and have an
octane rating no lower than that re-
commended for unleaded gasoline.
. If an oxygenate-blend, excepting a
methanol blend, is used, it should con-
tain no more than 15% oxygenate.
. If a methanol blend is used, it should
contain no more than 5% methanol
(methyl alcohol, wood alcohol). It should
also contain a suitable amount of ap-
propriate cosolvents and corrosion in-
hibitors. If not properly formulated with
appropriate cosolvents and corrosion
inhibitors, such methanol blends may
cause fuel system damage and/or vehi-
cle performance problems. At this time,
sufficient data is not available to ensure
that all methanol blends are suitable for
use in INFINITI vehicles.
If any undesirable driveability problems such
as engine stalling or hard hot starting are
experienced after using oxygenate-blend
fuels, immediately change to a non-oxyge-
nate fuel or a fuel with a low blend of MTBE.
Take care not to spill gasoline during
refueling. Gasoline containing oxygenates can cause paint damage.
E-15 fuel
E-15 fuel is a mixture of approximately 15%
fuel ethanol and 85% unleaded gasoline. E-
15 can only be used in vehicles designed to
run on E-15 fuel. Do not use E-15 in your
vehicle. U.S. government regulations require
fuel ethanol dispensing pumps to be identi-
fied with small, square, orange and black
label with the common abbreviation or the
appropriate percentage for that region.
E-85 fuel
E-85 fuel is a mixture of approximately 85%
fuel ethanol and 15% unleaded gasoline. E-
85 can only be used in a Flexible Fuel Vehicle
(FFV). Do not use E-85 fuel in your vehicle.
U.S. government regulations require fuel
ethanol dispensing pumps to be identified
by a small, square, orange and black label
with the common abbreviation or the appro-
priate percentage for that region.
Fuel containing MMT
MMT, or methylcyclopentadienyl manga-
nese tricarbonyl, is an octane boosting
additive. INFINITI does not recommend the
use of fuel containing MMT. Such fuel may
adversely affect vehicle performance, in-
cluding the emissions control system. Note
that while some fuel pumps label MMTcontent, not all do, so you may have to
consult your gasoline retailer for more de-
tails.
Aftermarket fuel additives
INFINITI does not recommend the use of any
aftermarket fuel additives (Example: fuel
injector cleaner, octane booster, intake valve
deposit removers, etc.) which are sold com-
mercially. Many of these additives intended
for gum, varnish or deposit removal may
contain active solvent or similar ingredients
that can be harmful to the fuel system and
engine.
Octane rating tips
Using unleaded gasoline with an octane
rating lower than recommended above can
cause persistent, heavy spark knock. (Spark
knock is a metallic rapping noise.) If severe,
this can lead to engine damage. If you
detect a persistent heavy spark knock even
when using gasoline of the stated octane
rating, or if you hear steady spark knock
while holding a steady speed on level roads,
it is recommended you have an INFINITI
retailer correct the condition. Failure to
correct the condition is misuse of the
vehicle, for which INFINITI is not respon-
sible.
Incorrect ignition timing will result in knock-
ing, after-run or overheating. This in turn
Technical and consumer information10-5

10-8Technical and consumer information
ENGINE
ModelVR30DDTT
Type Gasoline, 4-cycle
Cylinder arrangement 6-cylinder, V-slanted at 60°
Bore × Stroke in (mm) 3.386× 3.386
(86.0 × 86.0)
Displacement cu in (cm
3)182.88 (2,997)
Firing order 1-2-3-4-5-6
Idle speed rpm
No adjustment is necessary.
Ignition timing
(B.T.D.C.) degree/rpm
Spark plug DILKAR8K8G
Spark plug gap (Normal) in (mm) 0.031 (0.8)
Camshaft operation Timing chain
This spark ignition system complies with the Canadian standard ICES-002.
STI0425
SPECIFICATIONS