check engine INFINITI QX80 2018 Repair Manual

8-12Do-it-yourself
DI0137MA
Check the fluid level in each cell (Remove the
battery cover if it is necessary). It should be
between the UPPER LEVEL
and LOWER
LEVELlines.
If it is necessary to add fluid, add only
distilled water to bring the level to the
indicator in each filler opening. Do not
overfill.
SDI1480C
1. Remove the cell plugs.
2. Add distilled water up to the UPPER LEVEL
line.
If the side of the battery is not clear,
check the distilled water level by looking
directly above the cell; the condition
indicates OK and the conditionsneeds
more to be added.
3. Tighten cell plugs
.
Vehicles operated in high temperatures or
under severe conditions require frequent
checks of the battery fluid level.
JUMP STARTING
If jump starting is necessary, see “Jump
starting” (P.6-11). 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.
SDI2533
1. Power steering fluid pump
2. Water pump
3. Alternator
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. 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.
Do-it-yourself8-13
VARIABLE VOLTAGE CONTROL SYSTEMDRIVE BELTS

If the brakes do not operate properly, have
the brakes checked. It is recommended that
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.
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 schedules shown in the “9.
Maintenance and schedules” section.
BRAKE BOOSTER
Check the brake booster function as follows:
1. With the engine off, depress and release the foot brake pedal more than 20 times.
When the foot brake pedal movement
(distance of travel) remains the same
from one pedal application to the next,
continue on to the next step.
2. While depressing the foot brake pedal, start the engine.
3. With the foot brake pedal depressed, stop the engine. Keep the pedal de-
pressed for about 30 seconds.
4. Run the engine for 1 minute without depressing the foot brake pedal, then
turn it off. Depress the foot brake pedal
several times. The pedal travel distance
will decrease gradually with each de-
pression as the hydraulic pressure de-
creases. If the brakes do not operate properly, have
the brakes checked. It is recommended that
you visit an INFINITI retailer for repair.
Do-it-yourself8-17
BRAKES

8-18Do-it-yourself
SDI2518
SDI2532
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 pushed to the OFF or LOCK position and the
headlight switch is turned to OFF.
2. Open the engine hood and remove the cover on the battery.
3. Remove the fuse/fusible link holder cover
,or.
4. Remove the fuse with the fuse puller.
SDI1753
Type A
SDI1754
Type B
FUSES

9-2Maintenance and schedules
Some day-to-day and regular maintenance
is essential to maintain your vehicle’s 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.
You can be confident that an INFINITI
retailer’s service department performs the
best job to meet the maintenance require-
ments 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. It is
recommended to have an INFINITI retailer
do it promptly. In addition, it is recom-
mended 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).
EXPLANATION OF MAINTE-
NANCE 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.
MAINTENANCE REQUIREMENT GENERAL MAINTENANCE

9-4Maintenance and schedules
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.
Engine drive belt*: 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) for exhaust gas (carbon
monoxide).)
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.
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 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 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 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.8-4) 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.
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.
Maintenance and schedules9-5
EXPLANATION OF SCHEDULED
MAINTENANCE ITEMS

10-6Technical and consumer information
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.

down condition; check for improper
tongue load, overload, worn suspension
or other possible causes of either condi-
tion.
. Always secure items in the trailer to
prevent load shift while driving.
. Keep the cargo load as low as possible in
the trailer to keep the trailer center of
gravity low.
. Load the trailer so approximately 60% of
the trailer load is in the front half and
40% is in the back half. Also make sure
the load is balanced side to side.
. Check your hitch, trailer tire pressure,
vehicle tire pressure, trailer light opera-
tion, and trailer wheel lug nuts every time
you attach a trailer to the vehicle.
. Be certain your rearview mirrors conform
to all federal, state or local regulations. If
not, install any mirrors required for
towing before driving the vehicle.
. Determine the overall height of the
vehicle and trailer so the required clear-
ance is known.
Trailer towing tips
In order to gain skill and an understanding of
the vehicle’s behavior, you should practice
turning, stopping and backing up in an area
which is free from traffic. Steering stability,
and braking performance will be somewhat different than under normal driving condi-
tions.
.
Always secure items in the trailer to
prevent load shift while driving.
. Lock the trailer hitch coupler with a pin or
lock to prevent the coupler from inad-
vertently becoming unlatched.
. Avoid abrupt starts, acceleration or
stops.
. Avoid sharp turns or lane changes.
. Always drive your vehicle at a moderate
speed. Some states or provinces have
specific speed limits for vehicles that are
towing trailers. Obey the local speed
limits.
. When backing up, hold the bottom of the
steering wheel with one hand. Move
your hand in the direction in which you
want the trailer to go. Make small
corrections and back up slowly. If possi-
ble, have someone guide you when you
are backing up.
Always block the wheels on both vehicle and
trailer when parking. Parking on a slope is
not recommended; however, if you must do
so:
CAUTION
If you move the shift lever to the P
(Park) position before blocking the
wheels and applying the parking brake,
transmission damage could occur.
1. Apply and hold the brake pedal.
2. Have someone place blocks on the downhill side of the vehicle and trailer
wheels.
3. After the wheel blocks are in place, slowly release the brake pedal until the
blocks absorb the vehicle load.
4. Apply the parking brake.
5. Shift the transmission into P (Park).
6. Four-Wheel Drive (4WD) models:
Make sure that the 4WD shift switch is
engaged in the AUTO, 4HI or 4LO
position and the Automatic Transmission
(AT) park warning light is turned off.
7. Turn off the engine.
To drive away:
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift the transmission into gear.
Technical and consumer information10-27

— the Forward Emergency Braking(FEB) with pedestrian detection sys-
tem
— the Predictive Forward Collision Warning (PFCW) system
. 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
after 50 miles (80 km) of travel and at
every break.
. When launching a boat, do not 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, the transmission
fluid should be changed more frequently.
For additional information, see “9. Main-
tenance and schedules” section.
TOW mode
Using TOW mode is recommended when
pulling a heavy trailer or hauling a heavy
load. Push the TOW mode switch to activate
TOW mode. The TOW mode indicator light
in the meter illuminates when TOW mode is
selected. Push the TOW mode switch again to turn TOW mode off. TOW mode is
automatically cancelled when the ignition
switch is placed in the OFF position.
TOW mode includes the following features:
.
Grade logic — Adjusts transmission shifts
when pulling a trailer or hauling a load up
a grade.
. Downhill Speed Control (DSC) — auto-
matically downshifts when driving down
a grade with a trailer or heavy load to
help control vehicle speed.
Driving the vehicle in the TOW mode with no
trailer/load or light trailer/light load will not
cause any damage. However, fuel economy
may be reduced and the transmission/
engine driving characteristics may feel unu-
sual.
When towing a trailer, the transmission
fluid should be changed more frequently.
For additional information, see “9. Main-
tenance and schedules” section.
Trailer Sway Control
To minimize trailer sway, your vehicle may
apply braking to individual wheels based on
input from your vehicle sensors and vehicle
speed. Trailer Sway Control is a function of
the Vehicle Dynamic Control (VDC) system
and is active when the VDC function is
enabled.
CAUTION
If the VDC OFF switch is on (meaning
VDC system OFF), the Trailer Sway
Control is also disabled.
When Trailer Sway Control is in operation,
the VDC warning light blinks. When vehicle
control is regained, VDC warning light will
turn OFF.
For additional information about the VDC
system, see “Vehicle Dynamic Control (VDC)
system” (P.5-133).
If Trailer Sway Control activates:
1. Take your foot off the accelerator pedal to allow the vehicle to coast and steer as
straight ahead as the road conditions
allow. This combination will help stabilize
the vehicle.
CAUTION
Do not try to correct trailer sway by
steering or applying the brakes.
2. When the trailer sway stops, gently apply the brakes and pull to the side of
the road in a safe area.
Technical and consumer information10-29