check engine INFINITI Q50 2021 Repair Manual

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

8-16Do-it-yourself
SDI2048
REPLACING
Replace the wiper blades if they are worn.
Before replacing the wiper blades, the wiper
should be in the fully up position to avoid
scratching the engine hood or damaging the
wiper arm. To pull up the wiper arm, see
“Wiper and washer switch” (P.2-32).
1. Pull the wiper arm.
2. Push the release tab
, and then move
the wiper blade down the wiper arm
while pushing the release tab to remove.
3. Insert the new wiper blade onto the wiper arm until a click sounds.
4. Rotate the wiper blade so the dimple is in the groove.
CAUTION
.After wiper blade replacement, re-
turn the wiper arm to its original
position;
otherwise it may be damaged when
the hood is opened.
. Make sure the wiper blades contact
the glass; otherwise the arm may be
damaged from wind pressure. If the brakes do not operate properly, have
the brakes checked. It is recommended you
visit an INFINITI retailer for this service.
SELF-ADJUSTING BRAKES
Your vehicle is equipped with self-adjusting
brakes.
The disc-type brakes self-adjust every time
the brake pedal is applied.
WARNING
Have your brake system checked if the
brake pedal height does not return to
normal. It is recommended you visit an
INFINITI retailer for this service.
BRAKE PAD WEAR WARNING
The disc brake pads have audible wear
warnings. When a brake pad requires repla-
cement, it will make a high pitched scraping
sound when the vehicle is in motion. This
scraping sound will first occur only when the
brake pedal is depressed. After more wear of
the brake pad, the sound will always be
heard even if the brake pedal is not
depressed. Have the brakes checked as soon
as possible if the wear warning sound is
heard.
BRAKES

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

9-2Maintenance and schedules
Some day-to-day and regular maintenance
is essential to maintain your vehicle in good
mechanical condition, as well as its emission
and engine performance.
It is the owner’s responsibility to make sure
that the scheduled maintenance, as well as
general maintenance, is performed.
As the vehicle owner, you are the only one
who can ensure that your vehicle receives
the proper maintenance. You are a vital link
in the maintenance chain.
GENERAL MAINTENANCE
General maintenance includes those items
which should be checked during normal day-
to-day operation. They are essential for
proper vehicle operation. It is your respon-
sibility to perform these procedures regularly
as prescribed.
Performing general maintenance checks re-
quires minimal mechanical skill and only a
few general automotive tools.
These checks or inspections can be done by
yourself, a qualified technician or, if you
prefer, an INFINITI retailer.
SCHEDULED MAINTENANCE
The maintenance items listed in this section
are required to be serviced at regular inter-
vals. However, under severe driving condi-
tions, additional or more frequent
maintenance will be required.
WHERE TO GO FOR SERVICE
If maintenance service is required or your
vehicle appears to malfunction, have the
systems checked and serviced. It is recom-
mended you visit an INFINITI retailer for this
service.
INFINITI technicians are well-trained spe-
cialists and are kept up to date with the
latest service information through technical
bulletins, service tips and training programs.
They are completely qualified to work on
INFINITI vehiclesbeforework begins.
If your vehicle is involved in a collision, it is
recommended that you ask your INFINITI
retailer where the nearest INFINITI Certified
Collision Center is located, or go to http://
collision.infinitiusa.com.
You can be confident that an INFINITI
retailer’s service department can perform
the service needed to meet the maintenance
requirements on your vehicle. During the normal day-to-day operation of
the vehicle, general maintenance should be
performed regularly as prescribed in this
section. If you detect any unusual sounds,
vibrations or smells, be sure to check for the
cause and have it checked promptly. In
addition, it is recommended you visit an
INFINITI retailer if you think that repairs are
required.
When performing any checks or mainte-
nance work, closely observe “Maintenance
precautions” (P.8-2) of this manual.
EXPLANATION OF GENERAL
MAINTENANCE ITEMS
Additional information on the following
items with “*” is found in the “8. Do-it-
yourself” section of this manual.
Outside the vehicle
The maintenance items listed here should be
performed from time to time, unless other-
wise specified.
Doors and engine hood:
Check that all doors
and the engine hood, operate properly. Also
ensure that all latches lock securely. Lubri-
cate hinges, latches, latch pins, rollers and
links if necessary. Make sure that the
secondary latch keeps the hood from open-
ing when the primary latch is released.
When driving in areas using road salt or
MAINTENANCE REQUIREMENT GENERAL MAINTENANCE

9-4Maintenance and schedules
and smoothly, and are installed securely.
Check the belt webbing for cuts, fraying,
wear or damage.
Steering wheel:Check for changes in the
steering conditions, such as excessive free
play, hard steering or strange noises.
Warning lights and chimes: Make sure that
all warning lights and chimes are operating
properly.
Windshield defroster: Check that the air
comes out of the defroster outlets properly
and in sufficient quantity when operating
the heater or air conditioner.
Windshield wiper and washer*: Check that
the wipers and washer operate properly and
that the wipers do not streak.
Under the hood and vehicle
The maintenance items listed here should be
checked periodically (for example, each time
you check the engine oil or refuel).
Battery*: Check the fluid level in each cell. It
should be between the MAX and MIN lines.
Vehicles operated in high temperatures or
under severe condition require frequent
checks of the battery fluid level.
NOTE:
Care should be taken to avoid situations
that can lead to potential battery discharge
and potential no-start conditions such as: 1.
Installation or extended use of electro-
nic accessories that consume battery
power when the engine is not running
(Phone chargers, GPS, DVD players,
etc.)
2. Vehicle is not driven regularly and/or
only driven short distances.
In these cases, the battery may need to be
charged to maintain battery health.
Brake fluid level*: Make sure that the brake
fluid level is between the MAX and MIN lines
on the reservoir.
Engine coolant level*: Check the coolant
level when the engine is cold.
Intercooler coolant level*: Check the coolant
level when the engine is cold.
Engine drive belts*: Make sure that no belt is
frayed, worn, cracked or oily.
Engine oil level*: Check the level after
parking the vehicle on a level spot and
turning off the engine. Wait more than 15
minutes for the oil to drain back into the oil
pan.
Exhaust system: Make sure there are no
loose supports, cracks or holes. If the sound
of the exhaust seems unusual or there is a
smell of exhaust fumes, immediately have
the exhaust system inspected. It is recom-
mended you visit an INFINITI retailer for this
service. (See “Precautions when starting and driving” (P.5-4).)
Fluid leaks:
Check under the vehicle for fuel,
oil, water or other fluid leaks after the
vehicle has been parked for a while. Water
dripping from the air conditioner after use is
normal. If you should notice any leaks or if
gasoline fumes are evident, check for the
cause and have it corrected immediately.
Radiator and hoses: Check the front of the
radiator and clean off any dirt, insects,
leaves, etc., that may have accumulated.
Make sure the hoses have no cracks, defor-
mation, rot or loose connections.
Underbody: The underbody is frequently
exposed to corrosive substances such as
those used on icy roads or to control dust. It
is very important to remove these sub-
stances, otherwise rust will form on the
floor pan, frame, fuel lines and around the
exhaust system. At the end of winter, the
underbody should be thoroughly flushed
with plain water, being careful to clean
those areas where mud and dirt may accu-
mulate. For additional information, see
“Cleaning exterior” (P.7-2).
Windshield washer fluid*: Check that there
is adequate fluid in the reservoir.

The following descriptions are provided to
give you a better understanding of the
scheduled maintenance items that should
be regularly checked or replaced. The main-
tenance schedule indicates at which mile-
age/time intervals each item requires
service.
In addition to scheduled maintenance, your
vehicle requires that some items be checked
during normal day-to-day operation. Refer
to “General maintenance” (P.9-2).
Items marked with “*” are recommended by
INFINITI for reliable vehicle operation. You
are not required to perform maintenance on
these items in order to maintain the warran-
ties which come with your vehicle. Other
maintenance items and intervals are re-
quired.
When applicable, additional information can
be found in the “8. Do-it yourself” section of
this manual.
NOTE:
INFINITI does not advocate the use of non-
OEM approved aftermarket flushing sys-
tems and strongly advises against perform-
ing these services on an INFINITI product.
Many of the aftermarket flushing systems
use non-OEM approved chemicals or sol-
vents, the use of which has not been
validated by INFINITI.
For recommended fuel, lubricants, fluids,grease, and refrigerant, refer to “Capacities
and recommended fluids/lubricants” (P.10-
2) of this manual.
EMISSION CONTROL SYSTEM
MAINTENANCE
Drive belts*:
Check engine drive belts for wear, fraying or
cracking and for proper tension. Replace any
damaged drive belts.
Engine air filter:
Replace at specified intervals. When driving
for prolonged periods in dusty conditions,
check/replace the filter more frequently.
Engine coolant*:
Replace coolant at the specified interval.
When adding or replacing coolant, be sure to
use only Genuine NISSAN Long Life Anti-
freeze/Coolant (blue) or equivalent with the
proper mixture. (Refer to “Engine cooling
system” (P.8-3) to determine the proper
mixture for your area.)
NOTE:
Mixing any other type of coolant or the use
of non-distilled water may reduce the
recommended service interval of the cool-
ant.
Intercooler coolant:
Intercooler coolant is maintenance-free.
Engine oil and oil filter:
Replace engine oil and oil filter at the
specified intervals. For recommended oil
grade and viscosity refer to “Capacities and
recommended fluids/lubricants” (P.10-2).
Engine valve clearance*:
Inspect only if valve noise increases. Adjust
valve clearance if necessary.
Evaporative emissions control vapor lines*:
Check vapor lines for leaks or looseness.
Tighten connections or replace parts as
necessary.
Fuel lines*:
Check the fuel hoses, piping and connections
for leaks, looseness, or deterioration. Tight-
en connections or replace parts as necessary.
Spark plugs:
Replace at specified intervals. Install new
plugs of the type as originally equipped.
CHASSIS AND BODY MAINTE-
NANCE
Brake lines and cables:
Visually inspect for proper installation.
Check for chafing, cracks, deterioration,
and signs of leaking. Replace any deterio-
rated or damaged parts immediately.
Brake pads, rotors, drums and linings:
Maintenance and schedules9-5
EXPLANATION OF SCHEDULED
MAINTENANCE ITEMS

10-6Technical and consumer information
may cause excessive fuel consumption or
damage to the engine. If any of the above
symptoms are encountered, have your ve-
hicle checked. It is recommended you visit an
INFINITI retailer for servicing.
However, now and then you may notice
light spark knock for a short time while
accelerating or driving up hills. This is no
cause for concern, because you get the
greatest fuel benefit when there is light
spark knock for a short time under heavy
engine load.
JVT0342X
API certification mark
API service symbol
ENGINE OIL AND OIL FILTER
RECOMMENDATION
Selecting the correct oil
It is essential to choose the correct grade,
quality, and viscosity engine oil to ensure
satisfactory engine life and performance,
see “Capacities and recommended fluids/
lubricants” (P.10-2). INFINITI recommends
the use of an energy conserving oil in order
to improve fuel economy.
Select only engine oils that meet the Amer-
ican Petroleum Institute (API) certificationor International Lubricant Standardization
and Approval Committee (ILSAC) certifica-
tion and SAE viscosity standard. These oils
have the API certification mark on the front
of the container. Oils which do not have the
specified quality label should not be used as
they could cause engine damage.Oil additives
INFINITI does not recommend the use of oil
additives. The use of an oil additive is not
necessary when the proper oil type is used
and maintenance intervals are followed.
Oil which may contain foreign matter or has
been previously used should not be used.

wwwapps.tc.gc.ca/Saf-Sec-Sur/7/
PCDB-BDPP/fc-cp.aspx?lang=fra
(French speakers).
Additional information concerning
motor vehicle safety may be obtained
from Transport Canada’s Road
Safety Information Centre at 1-
800-333-0371 or online at www.tc.
gc.ca/ roadsafety (English speakers)
or www.tc.gc.ca/securiteroutiere
(French speakers).
To notify INFINITI of any safety
concerns please contact our Consu-
mer Information Centre toll free at 1-
800- 361-4792.
WARNING
A vehicle equipped with Intelligent All-
Wheel Drive (AWD) should never be
tested using a two wheel dynamometer
(such as the dynamometers used by
some states for emissions testing), or
similar equipment. Make sure you inform
test facility personnel that your vehicle
is equipped with AWD before it is placed
on a dynamometer. Using the wrong test
equipment may result in transmission
damage or unexpected vehicle move-
ment which could result in serious vehicle
damage or personal injury.
Due to legal requirements in some states/
areas, your vehicle may be required to be in
what is called the “ready condition” for an
Inspection/Maintenance (I/M) test of the
emission control system.
The vehicle is set to the “ready condition”
when it is driven through certain driving
patterns. Usually, the “ready condition” can
be obtained by ordinary usage of the vehicle.
If a powertrain system component is re-
paired or the battery is disconnected, the
vehicle may be reset to a “not ready condi-
tion”. Before taking the I/M test, check the
vehicle’s inspection/maintenance test readi- ness condition. Place the ignition switch in
the ON position without starting the engine.
If the Malfunction Indicator Light (MIL)
comes on steady for 20 seconds and then
blinks for 10 seconds, the I/M test condition
is “not ready”. If the MIL does not blink after
20 seconds, the I/M test condition is
“ready”.
It is recommended you visit an INFINITI
retailer to set the “ready condition” or to
prepare the vehicle for testing.
Technical and consumer information10-23
READINESS FOR INSPECTION/
MAINTENANCE (I/M) TEST (US only)

11 Index
A
ABS (Anti-lock Braking System) ................... 5-126
Active Lane Control ............................................ 5-25
Active noise cancellation ................................. 5-137
Active sound enhancement ............................ 5-137
Active trace control .......................................... 5-129
Air bag systemFront-seat mounted side-impact
upplemental air bag system ....................... 1-57
Roof-mounted curtain side-impact
supplemental air bag system ..................... 1-57
Air bag warning labels ....................................... 1-60
Air bag warning light .............................. 1-60, 2-12
Air cleaner housing filter ................................... 8-15
Air conditioner
Air conditioner operation ............................ 4-36
Air conditioner service ................................ 4-42
Air conditioner specification label ......... 10-13
Air conditioning system refrigerant and
lubricant recommendations ....................... 4-42
Air conditioning system refrigerant and
oil recommendations .................................... 10-7
Automatic air conditioner ........................... 4-37
DUAL mode setting ..................................... 4-40
Heater and air conditioner .......................... 4-36
Servicing air conditioner ............................. 4-42
Air deflectors ...................................................... 10-16 Alarm
How to stop alarm (see vehicle
security system) ............................................. 2-31
Alcohol, drugs and driving ................................ 5-10
Android Auto .......................................................... 4-2
Antenna .................................................................. 4-43
Anti-lock Braking System (ABS) ................... 5-126
Appearance care
Exterior appearance care ............................... 7-2
Interior appearance care ................................ 7-5
Apple CarPlay
®...................................................... 4-2
Armrest ...................................................................... 1-7
Around View
®Monitor ...................................... 4-11
Audible reminders ................................................. 2-17
Autolight system .................................................. 2-36
Automatic Automatic air conditioner ........................... 4-37
Automatic Transmission Fluid (ATF) ......... 8-9
Driving with automatic transmission ....... 5-16
Automatic door locks ............................................ 3-5
Automatic seat positioner ................................ 3-33
Avoiding collision and rollover ............................ 5-9
B
Back-up Collision Intervention (BCI) .............. 5-60
Battery .................................................................... 8-11
Battery replacement, Intelligent Key ......... 3-2
Battery saver system .................................... 2-39
Intelligent Key ................................................. 8-19 Variable voltage control system ............... 8-13
Before starting the engine ................................ 5-14
Belts (See drive belts) ......................................... 8-13
Blind Spot Intervention
®(BSI) ......................... 5-48
Blind Spot Warning (BSW) .............................. 5-40
Brake
Anti-lock Braking System (ABS) ............. 5-126
Brake fluid ...................................................... 8-10
Brake force distribution ............................ 5-128
Brake system ................................................ 5-125
Parking brake operation ............................. 5-20
Brake warning light .............................................. 2-11
Break-in schedule .............................................. 5-118
Bulb check/instrument panel ............................ 2-11
Bulb replacement ................................................. 8-22
C
Camera aiding sonar function ......................... 4-25
Capacities and
recommended fluids/lubricants ....................... 10-2
Car phone or CB radio ....................................... 4-43
Card holder ............................................................ 2-50
Catalytic converter Three-way catalyst ......................................... 5-5
Changing intercooler coolant ............................. 8-6
Chassis control ................................................... 5-131
Check tire pressure warning ............................. 2-22
Checking intercooler coolant level .................... 8-6

11-2
Child restraints ..................................................... 1-22LATCH system ............................................... 1-24
Precautions on child restraints .................. 1-22
Child safety ............................................................ 1-19
Child safety rear door lock .................................. 3-6
Chimes Audible reminders .......................................... 2-17
Seat belt warning light
and chime ............................................. 1-14, 2-12
Circuit breaker
Fusible link ....................................................... 8-18
Cleaning exterior and interior .................... 7-2, 7-5
Climate control
Automatic air conditioner ........................... 4-37
Clock ...................................................................... 2-29
Coat hooks ............................................................ 2-51
Cockpit ...................................................................... 2-3
Cold weather driving ........................................ 5-134
Console box ........................................................... 2-50
Coolant Capacities and
recommended fluids/lubricants ................. 10-2
Changing engine coolant ............................... 8-5
Checking engine coolant level ...................... 8-4
Corrosion protection ............................................. 7-7
Courtesy light ....................................................... 2-59
Cruise control ....................................................... 5-69
Fixed speed cruise control (on
ICC system) ..................................................... 5-87
Intelligent Cruise Control (ICC) ................. 5-71
Cruise indicator .................................................... 2-23 Cup holders ........................................................... 2-48
Current fuel consumption ................................. 2-27
D
Daytime running light system .......................... 2-39
Defroster switch
Rear window and outside mirror
defroster switch ............................................. 2-35
Dimensions ......................................................... 10-10
Direct Adaptive Steering ................................. 5-123
Distance Control Assist (DCA) ........................ 5-91
Distance to empty ............................................... 2-27
Drive belts .............................................................. 8-13
Drive positioner .................................................... 3-33
Driver assist system indicator .......................... 2-24
Driving Cold weather driving ................................. 5-134
Driving with automatic transmission ....... 5-16
Precautions when starting and driving ..... 5-4
E
ECO drive indicator light .................................... 2-17
ECO mode ............................................................. 5-22
ECO pedal system ............................................... 5-22
EconomyFuel .................................................................. 5-119
Elapsed time ......................................................... 2-27
Elapsed time and trip odometer ..................... 2-27
Emergency Call (SOS) button .......................... 2-46
Emission control information label ............... 10-12 Emission control system warranty ............... 10-21
Engine
Before starting the engine .......................... 5-14
Break-in schedule ........................................ 5-118
Capacities and
recommended fluids/lubricants ................. 10-2
Changing engine coolant ............................... 8-5
Changing engine oil and filter ...................... 8-7
Checking engine coolant level ...................... 8-4
Checking engine oil level ............................... 8-7
Coolant temperature gauge ......................... 2-8
Emergency engine shut off ......................... 5-13
Engine block heater .................................... 5-135
Engine compartment check locations ........ 8-3
Engine cooling system ................................... 8-3
Engine oil ........................................................... 8-7
Engine oil and filter
replacement indicator ................................... 2-25
Engine oil and oil
filter recommendation .................................. 10-6
Engine oil viscosity ........................................ 10-7
Engine serial number ................................. 10-12
Engine specifications ................................... 10-8
Engine start operation indicator ............... 2-21
If your vehicle overheats ................................ 6-7
Remote engine start ..................................... 3-19
Remote engine start
operation indicator ........................................ 2-21
Starting the engine ....................................... 5-15
Engine coolant temperature gauge .................. 2-8