2021 NISSAN FRONTIER check engine

brake needs adjustment, it is recom-
mended that you visit a NISSAN dealer for
this service.
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.
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.
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 prop-
erly 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 batter-
ies)*: This vehicle is equipped with a sealed
maintenance free battery. It is recom-
mended that you visit a NISSAN dealer for
service.
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 elec-
tronic accessories that consume bat-
tery power when the engine is not run-
ning (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 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 belts*: Make sure the drive
belts are not frayed, worn, cracked or oily.
Engine oil level*: Check the level af ter
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, immedi-
ately have the exhaust system inspected. It
is recommended that you visit a NISSAN
dealer for this service. For additional infor-
mation, refer to “Exhaust gas (carbon mon-
oxide)” in the “Starting and driving” section
of this manual.
Fluid leaks: Check under the vehicle for
fuel, oil, water or other fluid leaks af ter the
vehicle has been parked for a while. Water
dripping from the air conditioner af ter use
is normal. If you should notice any leaks or if
fuel fumes are evident, check for the cause
and have it corrected immediately.
9-4Maintenance and schedules

Power steering fluid level* and lines:
Check the level when the fluid is cold, with
the engine off. Check the lines for proper
attachment, leaks, cracks, etc.
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 may 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, refer to
the “Appearance and care” section of this
manual.
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
maintenance schedule indicates at which
mileage/time intervals each item requires
service.
In addition to scheduled maintenance,
your vehicle requires that some items be
checked during normal day-to-day opera-
tion. For additional information, refer to
“General maintenance” in this section.
Items marked with
“*”are recommended
by NISSAN for reliable vehicle operation.
You are not required to perform mainte-
nance on these items in order to maintain
the warranties which come with your
NISSAN. Other maintenance items and in-
tervals are required.
When applicable, additional information
can be found in the “Do-it-yourself ” section
of this manual.NOTE:
NISSAN does not advocate the use of
non-OEM approved af termarket flush-
ing systems and strongly advises
against performing these services on a
NISSAN product. Many of the af termar-
ket flushing systems use non-OEM ap-
proved chemicals or solvents, the use of
which has not been validated by NISSAN.
For recommended fuel, lubricants, fluids,
grease, and refrigerant, refer to “Recom-
mended fluids/lubricants and capaci-
ties” in the “Technical and consumer in-
formation” section 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 inter-
vals. When driving for prolonged periods in
dusty conditions, check/replace the filter
more frequently.
EXPLANATION OF SCHEDULED
MAINTENANCE ITEMS
Maintenance and schedules9-5

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, refer to “Engine cooling system”
in the “Do-it-yourself ” section of this manual.)
NOTE: Mixing any other type of coolant
or the use of non-distilled water may re-
duce 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 refer
to “Recommended fluids/lubricants and
capacities” in the “Technical and consumer
information” section of this manual.
Evaporative emissions control vapor
lines*: Check vapor lines for leaks or loose-
ness. Tighten connections or replace parts
as necessary.
Fuel lines*: Check the fuel hoses, piping
and connections for leaks, looseness, or
deterioration. Tighten connections or re-
place 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,
deterioration and fluid leaks. Replace any
deteriorated or damaged parts immedi-
ately.
Exhaust system: Visually inspect the ex-
haust pipes, muffler and hangers for leaks,
cracks, deterioration, and damage. Tighten
connections or replace parts as necessary.
Propeller shaf t(s): Check for damage,
looseness, and grease leakage.
In-cabin microfilter: Replace at specified
intervals. When driving for prolonged peri-
ods in dusty conditions, replace the filter
more frequently.
Steering gear and linkage, axle and sus-
pension parts, drive shaf t boots: Check
for damage, looseness, and leakage of oil
or grease. Under severe driving conditions,
inspect more frequently. Tire rotation:
Tires should be rotated every
7,500 miles (12,000 km). When rotating tires,
check for damage and uneven wear. Re-
place if necessary.
Transmission fluid/oil, differential oil: Vi-
sually inspect for signs of leakage at speci-
fied intervals.
Off-road maintenance: Check the follow-
ing items frequently whenever you drive
off-road through deep sand, mud or water:
• Brake pads and rotors
• Brake linings and drums
• Brake lines and hoses
• Differential, transmission and transfer case oil
• Steering linkage
• Propeller shaf t(s) and front drive shaf ts
• Engine air filter
• Clutch housing drain (AWD only)
9-6Maintenance and schedules

Fuel containing MMT
MMT, or methylcyclopentadienyl manga-
nese tricarbonyl, is an octane boosting ad-
ditive. NISSAN 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 MMT
content, not all do, so you may have to
consult your gasoline retailer for more de-
tails.
Af termarket fuel additives
NISSAN does not recommend the use of
any af termarket fuel additives (for ex-
ample, fuel injector cleaner, octane
booster, intake valve deposit removers,
etc.) which are sold commercially. Many of
these additives intended for gum, varnish
or deposit removal may contain active sol-
vents 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 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 recom-
mended that you have a NISSAN dealer
correct the condition. Failure to correct
the condition is misuse of the vehicle, for
which NISSAN is not responsible.
Incorrect ignition timing may result in
spark knock, af ter-run and/or overheating,
which may cause excessive fuel consump-
tion or engine damage. If any of the above
symptoms are encountered, have your ve-
hicle checked. It is recommended that you
visit a NISSAN dealer for servicing.However, now and then you may notice
light spark knock for a short time while
accelerating 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.
10-6Technical and consumer information

3. Try to rearrange the trailer load so it isbalanced as described in this section.
• Be careful when passing other vehicles. Passing while towing a trailer requires
considerably more distance than normal
passing. Remember, the length of the
trailer must also pass the other vehicle
before you can safely change lanes.
• Downshif t the transmission to a lower gear for engine braking when driving
down steep or long hills. This will help
slow the vehicle without applying the
brakes.
• Avoid holding the brake pedal down too long or too frequently. This could cause
the brakes to overheat, resulting in re-
duced braking efficiency.
• Increase your following distance to allow for greater stopping distances while tow-
ing a trailer. Anticipate stops and brake
gradually.
• NISSAN recommends that the cruise control not be used while towing a trailer.
• Some states or provinces have specific regulations and speed limits for vehicles
that are towing trailers. Obey the local
speed limits. • Check your hitch, trailer wiring harness
connections, and trailer wheel lug nuts
af ter 50 miles (80 km) of travel and at
every break.
• When launching a boat, don't allow the water level to go over the exhaust tail
pipe or rear bumper.
• Make sure you disconnect the trailer lights before backing the trailer into the
water or the trailer lights may burn out.
When towing a trailer, final drive gear oil
should be replaced and transmission oil/
fluid should be changed more fre-
quently. For additional information, refer
to the “Do-it-yourself ” section in this
manual.FLAT TOWING – 4WD WITH
AUTOMATIC TRANSMISSION
Towing a vehicle behind a recreational ve-
hicle, such as a motor home, is sometimes
called flat towing.

WARNING
A vehicle equipped with Four-Wheel
Drive (4WD) should never be tested us-
ing a two wheel dynamometer (such as
the dynamometers used by some
states for emissions testing), or similar
equipment. Make sure you inform the
test facility personnel that your vehicle
is equipped with 4WD before it is placed
on a dynamometer. Using the wrong
test equipment may result in transmis-
sion damage or unexpected vehicle
movement which could result in seri-
ous vehicle damage or personal injury.
Due to legal requirements in some states
and Canadian Provinces, 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 ve-
hicle. 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
readiness 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 af ter 20 seconds, the I/M test condi-
tion is “ready ”. It is recommended that you
visit a NISSAN dealer to set the “ready con-
dition” or to prepare the vehicle for testing.
This vehicle is equipped with an Event Data
Recorder (EDR). The main purpose of an
EDR is to record, in certain crash or near
crash-like situations, such as an air bag
deployment or hitting a road obstacle, data
that will assist in understanding how a ve-
hicle's systems performed. The EDR is de-
signed to record data related to vehicle dy-
namics and safety systems for a short
period of time, typically 30 seconds or less.
The EDR in this vehicle is designed to re-
cord such data as:
• How various systems in your vehicle were
operating;
• Whether or not the driver and passenger safety belts were buckled/fastened;
• How far (if at all) the driver was depress- ing the accelerator and/or brake pedal;
and,
• How fast the vehicle was traveling.
• Sounds are not recorded.
READINESS FOR INSPECTION/
MAINTENANCE (I/M) TEST EVENT DATA RECORDERS (EDR)
10-40Technical and consumer information

Parking brake operation.........5-19Self-adjusting brakes...........8-20Brake fluid....................8-11Brake system.................5-32Brakes......................8-20Break-in schedule...............5-21Brightness control
Instrument panel.............2-33Brightness/contrast button......4-9, 4-15Bulb check/instrument panel........2-15Bulb replacement...............8-28
C
C.M.V.S.S. certification label.........10-12Capacities and recommended
fuel/lubricants................ .10-2Car phone or CB radio............4-79Cargo
(See vehicle loading information).....10-14Cargo lamp switch..............2-34CD care and cleaning.............4-70CD player (See audio system).......4-54Child restraint with top tether strap. . . .1-32Child restraints.......1-25,1-26,1-28, 1-30Precautions on child
restraints.........1-39, 1-42, 1-54, 1-65Top tether strap anchor point
locations.................. .1-33Child safety rear door lock..........3-7Cleaning exterior and interior......7-2,7-4Clock set/adjustment..........4-7,4-13
Clock setting
(models with Navigation System).....4-13Cold weather driving.............5-40Compact disc (CD) player..........4-54Compass....................2-11Compass and outside temperature
display......................2-10Compass display...............2-10Connect phone................4-72Console box..................2-45Control panel buttons.........4-5, 4-10Back button.................4-13Brightness/contrast button. . . .4-9, 4-15Enter button..............4-5, 4-10Setting button...............4-13With navigation system.......4-10,4-11Controls
Audio controls (steering wheel).....4-71Heater and air conditioner controls. .4-34Heater and air conditioner controls
(manual)...................4-22CoolantCapacities and recommended
fuel/lubricants
...............10-2Changing engine coolant.........8-5Checking engine coolant level......8-5Engine coolant temperature gauge. . .2-7Corrosion protection..............7-7Cruise control.................5-19Cup holders................. .2-46Curtain side-impact and rollover
air bag..................... .1-82
D
Daytime Running Lights (DRL) system. .2-32Defroster switch
Rear window and outside mirror
defroster switch
..............2-29Rear window defroster switch.....2-29Dimensions and weights..........10-10Dimmer switch for instrument panel. . .2-33Display controls (see control panel
buttons)................. .4-5, 4-10Door locks................... .3-4Door open warning light...........2-17Drive belt....................8-15Driving
Cold weather driving...........5-40Driving with automatic
transmission................5-14Precautions when starting and
driving.....................5-2Driving the vehicle...............5-14
E
Economy - fuel.................5-23Electronic locking rear differential (E-Lock)
system.....................5-29Electronic locking rear differential (E-Lock)
system switch................ .2-37Emergency engine shutoff.......5-12,6-3Emission control information label. . . .10-12Emission control system warranty. . . .10-38
11-2

EngineBefore starting the engine........5-13Capacities and recommended
fuel/lubricants...............10-2Changing engine coolant.........8-5Changing engine oil............8-6Changing engine oil filter.........8-6Checking engine coolant level......8-5Checking engine oil level.........8-6Engine coolant temperature gauge. . .2-7Engine cooling system...........8-4Engine oil.................. .8-6Engine oil and oil filter
recommendation.............10-7Engine oil pressure warning light. . . .2-17Engine oil viscosity.............10-7Engine serial number...........10-11Engine specifications...........10-9Engine Block Heater.............5-41Engine coolant temperature gauge. . . .2-7Enter button...............4-5, 4-10Event Data recorders............10-40Exhaust gas (Carbon monoxide)......5-2Explanation of maintenance items.....9-2Explanation of scheduled maintenance
items...................... .9-5Extended storage switch..........8-23Eyeglass case.................2-45
F
First aid kit....................6-2
Flashers
(See hazard warning flasher switch). . . .6-2Flat tire.................. .6-3, 6-4Floor mat positioning aid...........7-6Fluid
Brake fluid..................8-11Capacities and recommended
fuel/lubricants...............10-2Engine coolant................8-4Engine oil.................. .8-6Power steering fluid............8-10Windshield-washer fluid.........8-12Fog light switch................2-33Front air bag system
(See supplemental restraint system). . .1-77Front power seat adjustment........1-5Front seats....................1-2Front-door pocket..............2-40Fuel
Capacities and recommended
fuel/lubricants
...............10-2Fuel economy................5-23Fuel gauge................. .2-8Fuel octane rating.............10-6Fuel recommendation..........10-4Fuel-filler cap................3-13Fuel-filler lid.................3-13Loose fuel cap warning..........2-6Fuel efficient driving tips...........5-21Fuel gauge................... .2-8Fuel-filler door.................3-13Fuses......................8-20Fusible links..................8-22
G
Garage door opener, HomeLink® Universal
Transceiver............2-56, 2-58, 2-59Gas cap.....................3-13Gauge
Engine coolant temperature gauge. . .2-7Fuel gauge................. .2-8Odometer.................. .2-5Speedometer................2-5Tachometer..................2-7Trip computer................2-9Trip odometer................2-5General maintenance.............9-2Glove box................... .2-44
H
Hands-free phone system, Bluetooth®. .4-96Hazard warning flasher switch........6-2Head restraints.................1-10Headlight and turn signal switch.....2-30Headlight control switch...........2-30Headlights...................8-26Heated seat switches............2-35Heater
Heater and air conditioner controls. .4-34Heater operation..........4-25, 4-35Hill descent control switch.........2-36Hill descent control system.........5-37Hill start assist system............5-38HomeLink® Universal
Transceiver............2-56, 2-58, 2-59
11-3