2021 HYUNDAI NEXO service

7-4
Maintenance
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You should exercise the utmost care
to prevent damage to your vehicle
and injury to yourself whenever per-
forming any maintenance or inspec-
tion procedures.
We recommend you have your vehi-
cle maintained and repaired by an
authorized HYUNDAI dealer. An
authorized HYUNDAI dealer meets
HYUNDAI's high service quality
standards and receives technical
support from HYUNDAI in order to
provide you with a high level of serv-
ice satisfaction.Owner's Responsibility
Maintenance service and record
retention are the owner's responsibil-
ity.
You should retain documents that
show proper maintenance has been
performed on your vehicle in accor-
dance with the scheduled mainte-
nance service charts shown on the
following pages. You need this infor-
mation to establish your compliance
with the servicing and maintenance
requirements of your vehicle war-
ranties.
Detailed warranty information is pro-
vided in your Owner's Handbook &
Warranty Information booklet.
Repairs and adjustments required as
a result of improper maintenance or
a lack of required maintenance are
not covered.
Owner Maintenance
Precautions
Inadequate, incomplete or insuffi-
cient servicing may result in opera-
tional problems with your vehicle that
could lead to vehicle damage, an
accident, or personal injury. This
chapter provides instructions only for
the maintenance items that are easy
to perform. Several procedures can
be done only by an authorized
HYUNDAI dealer with special tools.
Your vehicle should not be modified
in any way. Such modifications may
adversely affect the performance,
safety or durability of your vehicle
and may, in addition, violate condi-
tions of the limited warranties cover-
ing the vehicle.
Certain modifications may also be in
violation of regulations established
by the U.S. Department of
Transportation and other federal or
state agencies.
High voltage caution
Do not disassemble or perform
maintenance on the fuel cell
system unless you are quali-
fied. The fuel cell system can be
highly dangerous since there
are many high voltage parts
inside even if when power is off.
WARNING

7-5
7
Maintenance
Improper owner maintenance dur-
ing the warranty period may affect
warranty coverage. For details,
read the separate Owner's
Handbook & Warranty Information
booklet provided with the vehicle.
If you're unsure about any service
or maintenance procedure, have it
done by an authorized HYUNDAI
dealer.The following lists are vehicle checks
and inspections that should be per-
formed by the owner or an author-
ized HYUNDAI dealer at the frequen-
cies indicated to help ensure safe,
dependable operation of your vehi-
cle.
Any adverse conditions should be
brought to the attention of your deal-
er as soon as possible.
These Owner Maintenance vehicle
checks are generally not covered by
warranties and you may be charged
for labor, parts and lubricants used.
NOTICE
Performing maintenance work
on a vehicle can be dangerous.
If you lack sufficient knowledge
and experience or the proper
tools and equipment to do the
work, have it done by an author-
ized HYUNDAI dealer.
ALWAYS follow these precau-
tions for performing mainte-
nance work:
•Park your vehicle on level
ground, shift to the P (Park)
position, apply the parking
brake, and place the POWER
button in the OFF position.
Block the tires (front and
back) to prevent the vehicle
from moving.
Remove loose clothing or jew-
elry that can become entan-
gled in moving parts.
Keep flames, sparks, or smok-
ing materials away from the
battery related parts.
WARNING
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7-8
Maintenance
Normal Maintenance Schedule
Months1224364860728496108120132144156168180
Miles×1,00061218243036424854606672788490
Km×1,000102030405060708090100110120130140150
Hydrogen system
(Check the hydrogen leakage)Inspect every 6,000 miles (10,000 km) or 24 months
Air cleaner filterReplace every at 12,000 (20,000 km) miles
Device cooling coolantAt first, replace at 120,000 miles (200,000 km) or 10 years :
Thereafter, replace every 30,000 miles (48,000 km) or 24 months
Stack cooling coolantReplace every at 36,000 miles (60,000 km) or 36 months
Ion filterReplace every at 36,000 miles (60,000 km) or 36 months
Reduction gearNo check, No service required
Air conditioner refrigerant/
compressorIIIIIIIIIIIIIII
Brake lines, hoses and connectionsIIIIIIIIIIIIIII
Brake discs and padsIIIIIIIIIIIIIII
Driveshaft and bootsIIIIIII
Front suspension ball jointsIIIIIIIIIIIIIII
Maintenance Intervals
Maintenance
Item
I : Inspect and if necessary, adjust, correct, clean or replace.
R : Replace

7-10
Maintenance
Maintenance Under Severe Usage Conditions
The following items must be serviced more frequently on cars normally used under severe driving conditions. Refer
to the chart below for the appropriate maintenance intervals.
R : Replace I : Inspect and, after inspection, clean, adjust, repair or replace if neces\
sary
Maintenance itemMaintenanceoperationMaintenance intervalsDriving condition
Hydrogen system
(Check the hydrogen leakage)IInspect more frequently
depending on the conditionC, D, F, G, J, L
Air cleaner filterIInspect more frequently
depending on the conditionC, D, E
Device cooling coolantRReplace more frequently
depending on the conditionC, D, E, F, J, K, L
Stack cooling coolantRReplace more frequently
depending on the conditionC, D, F, G, L
Ion filterRReplace more frequently
depending on the conditionC, D, F, G, L
Reduction gear fluidR72,000 miles (120,000 km)C, F, G, I, J
Air conditioner refrigerant/compressorIInspect more frequently
depending on the conditionC, D, F, G, L
Disc brakes and pads, calipers and rotorsIInspect more frequently
depending on the conditionC, D, E, G, H

7-24
Maintenance
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Blade Inspection
Contamination of either the wind-
shield or the wiper blades with for-
eign matter can reduce the effective-
ness of the windshield wiper func-
tionality. Common sources of con-
tamination are insects, tree sap, and
hot wax treatments used by some
commercial car washes. If the blades
are not wiping properly, clean both
the window and the blades with a
clean cloth dampened with washer
fluid.
To prevent damage to the wiper
blades, arms or other compo-
nents, do not:
Use gasoline, kerosene, paint
thinner, or other solvents on or
near them.
Attempt to move the wipers manually.
Use non-specified wiper blades.
Information
Commercial hot waxes applied by
automatic car washes have been
known to make the windshield diffi-
cult to clean.
Blade Replacement
When the wipers no longer clean
adequately, the blades may be worn
or cracked, and require replacement.
To prevent damage to the wiper
arms or other components, do not
attempt to move the wipers manu-
ally.
The use of a non-specified wiper
blade could result in wiper mal-
function and failure.
Front windshield wiper service positions
This vehicle has a "hidden" wiper
design which means that the wipers
cannot be lifted when they are in
their bottom resting position.
1. Within 20 seconds of turning off
the vehicle, lift and hold the wiper
lever up to the MIST position for
about 2 seconds until the wipers
move to the top wipe position.
2. At this time you can lift the wipers off the windshield.
3. Gently put the wipers back down onto the windshield.
4. Turn the wipers to any ON position to return the wipers to the bottom
resting position.
NOTICE
NOTICE
i
NOTICEOFE078038N

7-34
Maintenance
Wheel Replacement
When replacing the metal wheels for
any reason, make sure the new
wheels are equivalent to the original
factory units in diameter, rim width
and offset.
Tire Traction
Tire traction can be reduced if you
drive on worn tires, tires that are
improperly inflated or on slippery
road surfaces. Tires should be
replaced when tread wear indicators
appear. To reduce the possibility of
losing control, slow down whenever
there is rain, snow or ice on the road.
Tire Maintenance
In addition to proper inflation, correct
wheel alignment helps to decrease
tire wear. If you find a tire is worn
unevenly, have your dealer check the
wheel alignment.
When you have new tires installed,
make sure they are balanced. This
will increase vehicle ride comfort and
tire life. Additionally, a tire should
always be rebalanced if it is removed
from the wheel.
Tire Sidewall Labeling
This information identifies and
describes the fundamental charac-
teristics of the tire and also provides
the tire identification number (TIN)
for safety standard certification. The
TIN can be used to identify the tire in
case of a recall.

Tires degrade over time, even
when they are not being used.
Regardless of the remaining
tread, HYUNDAI recommends
that tires be replaced after six
(6) years of normal service.
When replacing tires (or
wheels), it is recommended to
replace the two front or two
rear tires (or wheels) as a pair.
Replacing just one tire can
seriously affect your vehicle's
handling.
Heat caused by hot climates
or frequent high loading con-
ditions can accelerate the
aging process. Failure to fol-
low this warning may cause
sudden tire failure, which
could lead to a loss of vehicle
control resulting in an acci-
dent.

7-37
7
Maintenance
6. Maximum load rating
This number indicates the maximum
load in kilograms and pounds that
can be carried by the tire. When
replacing the tires on the vehicle,
always use a tire that has the same
load rating as the factory installed
tire.
7. Uniform tire quality grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and maxi-
mum section width.
For example:
TREAD wear 200
TRACTION AA
TEMPERATURE A
Tread wear
The tread wear grade is a compara-
tive rating based on the wear rate of
the tire when tested under controlled
conditions on a specified govern-
ment test course. For example, a tire
graded 150 would wear one-and-a-
half times (1½) as well on the gov-
ernment course as a tire graded 100.
The relative performance of tires
depends upon the actual conditions
of their use, however, and may
depart significantly from the norm
due to variations in driving habits,
service practices and differences in
road characteristics and climate.
These grades are molded on the
sidewalls of passenger vehicle tires.
The tires available as standard or
optional equipment on your vehicle
may vary with respect to grade.
Traction - AA, A, B & C
The traction grades, from highest to
lowest, are AA, A, B and C. Those
grades represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on spec-
ified government test surfaces of
asphalt and concrete. A tire marked
C may have poor traction perform-
ance.The traction grade assigned to
this tire is based on straight-
ahead braking traction tests,
and does not include accelera-
tion, cornering, hydroplaning,
or peak traction characteristics.
WARNING

H9
Service plug
OFEQ018011
The FCEV system contains
many electronic components.
High voltage components like
cables and other parts may emit
electromagnetic waves. Even if
the electromagnetic cover
blocks electromagnetic emis-
sions, electromagnetic waves
may have an effect on electron-
ic appliances. If you park the
vehicle for a long time, the high
voltage battery or 12V battery
will discharge. You need to drive
the vehicle several times per
month. We recommend driving
at least 10 minutes or 2 miles (3
km) when you drive the vehicle.
If the high voltage battery is dis-
charged and if it is impossible
to jump start the vehicle contact
your HYUNDAI dealer.
CAUTION
When you start the FCEV sys-
tem in the "P" or "N" gear
position, the "Ready ( )"
indicator is illuminated in the
cluster. The driver can drive
the vehicle.
When you leave the vehicle,
you should turn off the sys-
tem or shift into the "P" posi-
tion. If you depress the accel-
erator pedal by mistake and
the vehicle is not in the "P"
position, the vehicle will move
abruptly. This may result in
serious injury or death.
WARNING
Never touch the service plug
under the rear seat.
The service plug is attached to
the high voltage battery system.
Touching the service plug will
result in death or serious injury.
Service personnel should fol-
low procedures in service man-
ual.
WARNING