2021 INFINITI QX50 check engine

• If the battery is labeled "do not open" it ismaintenance free and battery fluid should
not be checked. It is recommended that you
visit an INFINITI retailer or a qualified spe-
cialist workshop to confirm the battery's
performance.
• Keep the battery surface clean and dry. Clean the battery with a solution of baking
soda and water.
• Make certain the terminal connections are clean and securely tightened.
• If the vehicle is not to be used for 30 days or longer, disconnect the negative (-) bat-
tery terminal cable to prevent discharge.
NOTE:
Care should be taken to avoid situations
that can lead to potential battery dis-
charge and potential no-start conditions
such as:
1. Installation or extended use of electronic 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.
WARNING
• Do not expose the battery to flames, an
electrical spark or a cigarette. Hydrogen
gas generated by the battery is explo-
sive. Explosive gases can cause blindness
or injury. Do not allow battery fluid to
contact your skin, eyes, fabrics or
painted surfaces. Sulfuric acid can cause
blindness or injury. After touching a bat-
tery or battery cap, do not touch or rub
your eyes. Thoroughly wash your hands.
If the acid contacts your eyes, skin or
clothing, immediately flush with water
for at least 15 minutes and seek medical
attention.
• When working on or near a battery, al-
ways wear suitable eye protection and
remove all jewelry.
• Battery posts, terminals and related ac-
cessories contain lead and lead com-
pounds. Wash hands after handling.
• Keep battery out of the reach of children.
• Do not tip the battery.
NOTE:
Do not try to open the top of the battery.
This battery is not equipped with removable
vent caps.
Vehicles operated in high temperatures or
under severe conditions might present bat-
tery liquid loss. It is recommended that you
visit an INFINITI retailer for a proper battery
diagnosis and service in case of required.
LDI3229
Do-it-yourself8-13

1. Automatic tensioner pulley
2. Generator pulley
3. Water pump pulley
4. Air conditioner compressor pulley
5. Crankshaft pulley
WARNING
Be sure the ignition switch is in the OFF or
LOCK position before servicing drive belt.
The engine could rotate unexpectedly. 1. Visually inspect the belt for signs of un-
usual wear, cuts, or fraying. If the belt is in
poor condition, have it replaced. It is rec-
ommended that you visit an INFINITI re-
tailer for this service.
2. Have the belt checked regularly for condition.
REPLACING SPARK PLUGS
Iridium-tipped spark plugs
It is not necessary to replace iridium-tipped
OAspark plugs as frequently as conventional
type spark plugs because they last much lon-
ger. Follow the maintenance log shown in the
"Maintenance and schedules" section of this
manual. Do not service iridium-tipped spark
plugs by cleaning or regapping.
• Always replace spark plugs with recom-
mended or equivalent ones.
WDI0638SDI1895
DRIVE BELT SPARK PLUGS
Do-it-yourself8-15

If any electrical equipment does not operate,
check for an open fuse.
Fuses are used in the passenger and engine
compartment. Spare fuses are provided and
can be found in the passenger compartment
fuse box.
When installing a fuse make sure the fuse is
installed in the fuse box securely.ENGINE COMPARTMENT
WARNING
Never use a fuse of higher or lower amper-
age rating than that specified on the fuse
box cover. This could damage the electrical
system or electronic control units or cause
a fire. If any electrical equipment does not come on,
check for an open fuse.
1. Be sure the ignition switch and the head-
light switch are OFF.
2. Open the engine hood.
3. Remove the fuse box cover by pushing the tabs and lifting the cover up.
4. Remove the fuse with the fuse puller. The fuse puller is located in the fuse block in
the passenger compartment.
LDI2997LDI3174
FUSES
8-20Do-it-yourself

Some day-to-day and regular maintenance is
essential to maintain your vehicle good me-
chanical condition, as well as its emissions
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
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 responsi-
bility 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 pre-
fer, 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 mainte-
nance will be required.
WHERE TO GO FOR SERVICE
If maintenance service is required or your
vehicle appears to malfunction, have the sys-
tems checked and serviced. It is recom-
mended that you visit an INFINITI retailer for
this service.
INFINITI technicians are well-trained spe-
cialists and are kept up-to-date with the lat-
est service information through technical bul-
letins, service tips and training programs.
They are fully 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 retail-
er’s service department can perform the ser-
vice needed to meet the maintenance re-
quirements on your vehicle. During the normal day-to-day operation of
the vehicle, general maintenance should be
performed regularly as prescribed in this sec-
tion. If you detect any unusual sounds, vibra-
tions or smells, be sure to check for the cause
or have it checked promptly. In addition, it is
recommended that you visit an INFINITI re-
tailer if you think that repairs are required.
When performing any checks or maintenance
work, closely observe the “Maintenance pre-
cautions” in the “Do-it-yourself” section of
this manual.
EXPLANATION OF GENERAL
MAINTENANCE ITEMS
WARNING
Failure to follow the procedures listed
within this section may result in personal
injury.
Additional information on the following
items with“*”isfound in the “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.
MAINTENANCE REQUIREMENTS GENERAL MAINTENANCE
9-2Maintenance and schedules

Doors and engine hood:Check that the doors
and engine hood operate properly. Also en-
sure that all latches lock securely. Lubricate
hinges, latches, latch pins, rollers and links if
necessary. Make sure that the secondary
latch keeps the hood from opening when the
primary latch is released.
When driving in areas using road salt or other
corrosive materials, check lubrication
frequently.
Check that the gas stays or struts properly
and securely hold the hood, trunk, or rear
hatch in a fully open position. If the hood,
trunk, or rear hatch is not held open, have the
gas stays or struts replaced.
Lights*: Clean the headlights on a regular
basis. Make sure that the headlights, stop
lights, tail lights, turn signal lights, and other
lights are all operating properly and installed
securely. Also check headlight aim.
Road wheel nuts (lug nuts)*: When checking
the tires, make sure no wheel nuts are miss-
ing, and check for any loose wheel nuts.
Tighten if necessary.
Tire rotation*: Rotate tires at the specified
interval shown in the maintenance schedule. Tires*:
Check the pressure with a gauge of-
ten and always prior to long distance trips. If
necessary, adjust the pressure in all tires, in-
cluding the spare, to the pressure specified.
Check carefully for damage, cuts or excessive
wear.
Tire Pressure Monitoring System (TPMS)
transmitter components: Replace the TPMS
transmitter grommet seal, valve core and cap
when the tires are replaced due to wear or
age.
Wheel alignment and balance: If the vehicle
should pull to either side while driving on a
straight and level road, or if you detect un-
even or abnormal tire wear, there may be a
need for wheel alignment.
If the steering wheel or seat vibrates at nor-
mal highway speeds, wheel balancing may be
needed.
For additional information regarding tires, re-
fer to “Important Tire Safety Information”
(US) or “Tire Safety Information” (Canada) in
the INFINITI Warranty Information Booklet. Windshield:Clean the windshield on a regular
basis. Check the windshield at least every six
months for cracks or other damage. Have a
damaged windshield repaired by a qualified
repair facility. It is recommended that you have
a damaged windshield repaired by an INFINITI
retailer, or an INFINITI Certified Collision Cen-
ter. To locate a collision center in your area,
refer to http://collision.infinitiusa.com.
Windshield wiper blades*: Check for cracks
or wear if they do not wipe properly.
Inside the vehicle
The maintenance items listed here should be
checked on a regular basis, such as when
performing scheduled maintenance, cleaning
the vehicle, etc.
Accelerator pedal: Check the pedal for
smooth operation and make sure the pedal
does not catch or require uneven effort. Keep
the floor mat away from the pedal.
Brake pedal: Check the pedal for smooth op-
eration. If the brake pedal suddenly goes
down further than normal, the pedal feels
spongy or the vehicle seems to take longer to
stop, have your vehicle checked immediately.
It is recommended that you visit an INFINITI
retailer for this service. Keep the floor mat
away from the pedal.
Maintenance and schedules9-3

Brakes:Check that the brakes do not pull the
vehicle to one side when applied.
Continuously Variable Transmission (CVT) P
(Park) position mechanism: On a fairly steep
hill check that the vehicle is held securely with
the shift lever in the P (Park) position without
applying any brakes.
Parking brake: Check the parking brake op-
eration regularly. The vehicle should be se-
curely held on a fairly steep hill with only the
parking brake applied. If the parking brake
does not securely hold the vehicle, it is recom-
mended that you visit an INFINITI retailer for
service.
Seat belts: Check that all parts of the seat
belt system (for example, buckles, anchors,
adjusters and retractors) operate properly
and smoothly, and are installed securely.
Check the belt webbing for cuts, fraying,
wear or damage.
Seats: Check seat position controls such as
seat adjusters, seatback recliner, etc., to en-
sure they operate smoothly and all latches
lock securely in every position. Check that the
head restraints/headrests move up and
down smoothly and the locks (if so equipped)
hold securely in all latched positions. Steering wheel:
Check for changes in the
steering system, such as excessive free play,
hard steering or strange noises.
Warning lights and chimes: Make sure 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 (for maintenance free batteries)*:
This vehicle is equipped with a sealed main-
tenance free battery. It is recommended that
you visit an INFINITI retailer for this service.
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 electronic
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.
Engine drive belt*: Make sure the drive belt is
not 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.
9-4Maintenance and schedules

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 vali-
dated by INFINITI.
For recommended fuel, lubricants, fluids,
grease, and refrigerant, see “Recommended
fluids/lubricants and capacities” (P. 10-2).
EMISSION CONTROL SYSTEM
MAINTENANCE:
Drive belt*:Check engine drive belt for wear,
fraying or cracking and for proper tension.
Replace any damaged drive belt.
Engine air filter: Replace at specified inter-
vals. 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 Antifreeze/Coolant (blue) or
equivalent with the proper mixture. (For ad- ditional information on the proper mixture for
your area, see “Engine cooling system”
(P. 8-4).)
NOTE: Mixing any other type of coolant or
the use of non-distilled water may reduce
the recommended service interval of the
coolant.
Engine oil and oil filter:
Replace engine oil
and oil filter at the specified intervals. For
recommended oil grade and viscosity, see
“Recommended fluids/lubricants and capaci-
ties” (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 deterio-
ration. Tighten connections or replace parts
as necessary.
Spark plugs: Replace at specified intervals.
Install new plugs of the same type as origi-
nally equipped.
CHASSIS AND BODY
MAINTENANCE:
Brake lines and cables: Visually inspect for
proper installation. Check for chafing, cracks,
deterioration, and signs of leaking. Replace
any deteriorated or damaged parts
immediately.
Brake pads and rotors: Check for wear, de-
terioration and fluid leaks. Replace any dete-
riorated or damaged parts immediately.
Exhaust system: Visually inspect the exhaust
pipes, muffler and hangers for leaks, cracks,
deterioration, and damage. Tighten connec-
tions or replace parts as necessary.
In-cabin microfilter: Replace at specified in-
tervals. When driving for prolonged periods in
dusty conditions, replace the filter more
frequently.
Propeller shaft(s): Check for damage, loose-
ness, and grease leakage. (AWD)
Steering gear and linkage, axle and suspen-
sion parts, drive shaft boots: Check for dam-
age, looseness, and leakage of oil or grease.
Under severe driving conditions, inspect more
frequently.
9-6Maintenance and schedules

and black label with the common abbrevia-
tion 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 Ve-
hicle (FFV). Do not use E-85 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 appropriate
percentage for that region.
Fuel containing MMT
MMT, or methylcyclopentadienyl manganese
tricarbonyl, is an octane boosting additive.
INFINITI does not recommend the use of fuel
containing MMT. Such fuel may adversely
affect vehicle performance, including the
emissions control system. Note that while
some fuel pumps label MMT content, not all
do, so you may have to consult your gasoline
retailer for more details.
Aftermarket fuel additives
INFINITI does not recommend the use of any
aftermarket fuel additives (for 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 con-
tain active solvents or similar ingredients that
can be harmful to the fuel system and engine.
Octane rating tips
Using unleaded gasoline with an octane rat-
ing lower than recommended can cause per-
sistent, heavy “spark knock.” (“Spark knock”
is a metallic rapping noise.) If severe, this can
lead to engine damage. If you detect a per-
sistent 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 recom-
mended that you have an INFINITI retailer
correct the condition. Failure to correct the
condition is misuse of the vehicle, for which
INFINITI is not responsible.Incorrect ignition timing may result in spark
knock, after-run and/or overheating, which
may cause excessive fuel consumption or en-
gine damage. If any of the above symptoms
are encountered, have your vehicle checked.
It is recommended that you visit an INFINITI
retailer.
However, now and then you may notice light
spark knock for a short time while accelerat-
ing or driving up hills. This is not a cause for
concern, because you get the greatest fuel
benefit when there is light spark knock for a
short time under heavy engine load.
Technical and consumer information10-5