2023 HYUNDAI NEXO fuel

6-6
What to do in an emergency
The following items may need to be
reset after the battery has been dis-
charged or the battery has been dis-
connected. See chapter 3 or 4 for:
Power Windows
Trip Computer
Climate Control System
Clock
Audio System
Sunroof
Driver Position Memory System
External power source using 12V
battery
The use of external power acces-
sories may reduce performance
and function of the vehicle.
Especially, the use of dash cam-
eras may shut off the power of the
vehicle prior to the dash camera's
automatic shut-down.
If the power of the vehicle is shut
off, start the vehicle as explained.
(refer to "Using the 12V Battery
Switch")Jump Starting
In the event vehicle still does not
have a functional 12V battery (check
if interior lights will not turn on) then
you can try a jump start using a 12V
booster pack or jumper cables from
another vehicle's 12V battery
according to the following instruc-
tions.1. Position the vehicles close enough
that the jumper cables will reach,
but do not allow the vehicles totouch.
2. Avoid fans or any moving parts in the fuel cell power module com-
partment at all times, even when
the vehicles are turned off.
3. Turn off all electrical devices such as radios, lights, air conditioning,
etc. Put the vehicles in P (Park)
and set the parking brake. Turn
both vehicles OFF.
NOTICE
Jump starting can be danger-
ous if done incorrectly. Follow
the jump starting procedure in
this section to avoid serious
injury or damage to your vehi-
cle. If in doubt about how to
properly jump start your vehi-
cle, we strongly recommend
that you have a service techni-
cian or towing service do it for
you.
CAUTION

6-12
What to do in an emergency
Tire Pressure Monitoring System
Each tire, including the spare (if pro-
vided), should be checked monthlywhen cold and inflated to the inflation
pressure recommended by the vehi-
cle manufacturer on the vehicle plac-
ard or tire inflation pressure label. If
your vehicle has tires of a different
size than the size indicated on the
vehicle placard or tire inflation pres-
sure label, you should determine the
proper tire inflation pressure for
those tires.As an added safety feature, your
vehicle has been equipped with a tire
pressure monitoring system (TPMS)
that illuminates a low tire pressure
telltale when one or more of yourtires is significantly under-inflated.
Accordingly, when the low tire pres-
sure telltale illuminates, you should
stop and check your tires as soon as
possible, and inflate them to the
proper pressure. Driving on a signifi-cantly under-inflated tire causes the
tire to overheat and can lead to tire
failure. Under-inflation also reduces fuel effi-
ciency and tire tread life, and may
affect the vehicle's handling and
stopping ability.
Please note that the TPMS is not a
substitute for proper tire mainte-
nance, and it is the driver's responsi-bility to maintain correct tire pres-
sure, even if under-inflation has not
reached the level to trigger illumina-
tion of the TPMS low tire pressure
telltale.Your vehicle has also been equipped
with a TPMS malfunction indicator toindicate when the system is not
operating properly. The TPMS mal-function indicator is combined with
the low tire pressure telltale. Whenthe system detects a malfunction,
the telltale will flash for approximate-
ly one minute and then remain con-
tinuously illuminated. This sequence
will continue upon subsequent vehi-
cle start-ups as long as the malfunc-
tion exists. When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire pres-
sure as intended. TPMS malfunc-
tions may occur for a variety of rea-
sons, including the installation of
replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction telltale after replacing one or more
tires or wheels on your vehicle toensure that the replacement or alter-
nate tires and wheels allow the TPMS
to continue to function properly.
Over-inflation or under-inflation
can reduce tire life, adversely
affect vehicle handling, and
lead to sudden tire failure that
may cause loss of vehicle con-
trol resulting in an accident.
WARNING

7
Maintenance
7
Maintenance
Fuel Cell Power Module Compartment ...............7-3
Maintenance Services ...........................................7-4Owner's Responsibility .....................................................7-4
Owner Maintenance Precautions..................................7-4
Owner Maintenance ..............................................7-5 Owner Maintenance Schedule .......................................7-6
Scheduled Maintenance Services........................7-7 Normal Maintenance Schedule ......................................7-8
Maintenance Under Severe Usage Conditions ........7-10
Explanation of Scheduled Maintenance Items ..7-12
Device Cooling Coolant .......................................7-13 Checking the Coolant Level ..........................................7-13
Changing Coolant ............................................................7-15
Stack Cooling Coolant .........................................7-16 Checking the Coolant Level ..........................................7-16
Changing Coolant ............................................................7-18
Brake Fluid ............................................................7-19 Checking the Brake Fluid Level ...................................7-19
Washer Fluid .........................................................7-20 Checking the Washer Fluid Level................................7-20
Air Cleaner ............................................................7-20 Filter Replacement ..........................................................7-20
Climate Control Air Filter ....................................7-22 Filter Inspection ...............................................................7-22 Wiper Blades.........................................................7-24
Blade Inspection ..............................................................7-24
Blade Replacement .........................................................7-24
12V Battery ...........................................................7-27 Battery Recharging ........................................................7-28
Reset Features.................................................................7-28
Tires and Wheels .................................................7-29 Tire Care ............................................................................7-29
Recommended Cold Tire Inflation Pressures ...........7-30
Check Tire Inflation Pressure ......................................7-31
Tire Rotation.....................................................................7-32
Wheel Alignment and Tire Balance ............................7-33
Tire Replacement ............................................................7-33
Wheel Replacement ........................................................7-34
Tire Traction .....................................................................7-34
Tire Maintenance ............................................................7-34
Tire Sidewall Labeling ....................................................7-34
Tire Terminology and Definitions................................7-38
All Season Tires ...............................................................7-42
Summer Tires ...................................................................7-42
Snow Tires ........................................................................7-42
Radial-Ply Tires ...............................................................7-42
Low Aspect Ratio Tires..................................................7-43
7

7
Fuses ......................................................................7-45Instrument Panel Fuse Replacement..........................7-46
Fuel Cell Power Module Compartment Panel
Fuse Replacement ...........................................................7-47
Fuse/Relay Panel Description ......................................7-49
Light Bulbs ............................................................7-57 Headlamp, Front Center Lamp, Turn Signal Lamp,
Daytime Running Lamp, Parking Lamp,
Side Marker Replacement.............................................7-58
Side Repeater Lamp Replacement ..............................7-58
Rear Combination Light Bulb Replacement ..............7-59
High Mounted Stop Lamp .............................................7-59
License Plate Light Bulb Replacement ......................7-60
Interior Light Bulb Replacement .................................7-60
Appearance Care..................................................7-62 Exterior Care ....................................................................7-62
Interior Care .....................................................................7-67

7-3
7
Maintenance
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1. Brake fluid reservoir
2. Air cleaner
3. Fuse box
4. Windshield washer fluid reservoir
5. Device cooling coolant reservoir
6. Traction motor radiator cap
7. Stack cooling coolant reservoir
8. Fuel cell stack radiator cap
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The actual fuel cell power module compartment in the vehicle may differ from the illus- tration.

7-4
MaintenanceM
M AAIINN TTEENN AANN CCEE SS EE RR VV IICC EE SS
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 Service Passport. 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 forthe 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.
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

7-6
Maintenance
Owner Maintenance Schedule
When you stop for fuel:
• Check for both fuel cell stack andDevice cooling coolant level in
coolant reservoir.
Check the windshield washer fluid level.
Look for low or under-inflated tires.
While operating your vehicle:
Check for vibrations in the steering wheel. Notice if there is any
increased steering effort or loose-
ness in the steering wheel, or
change in its straight-ahead posi-tion.
Notice if your vehicle constantly turns slightly or "pulls" to one side
when traveling on smooth, levelroad.
When stopping, listen and check for unusual sounds, pulling to one
side, increased brake pedal travel
or "hard-to-push" brake pedal.
If any slipping or changes in the operation of your reduction gear
occurs, check the reduction gear
fluid level.
Check the reduction gear P (Park) function.
Check the parking brake.
Check for fluid leaks under your vehicle (water dripping from the air
conditioning system during or after
use is normal).
At least monthly:
Check coolant level in the coolantreservoir.
Check the operation of all exterior lights, including the brake lights,
turn signals and hazard warning
flashers.
Check the inflation pressures of all tires that are worn, show uneven
wear, or are damaged.
Check for loose wheel lug nuts.
At least twice a year: (i.e., every Spring and Fall)
Check radiator, heater and air con- ditioning hoses for leaks or dam-
age.
Check windshield washer spray and wiper operation. Clean wiper
blades with clean cloth dampened
with washer fluid.
Check headlamp alignment.
Check the seat belts for wear and function.
Be careful when checking the
coolant level when the fuel cell
power module is hot. Scalding
hot coolant and steam may
blow out under pressure. This
could cause burns or other seri-
ous injury.
WARNING

7-13
7
Maintenance
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The high-pressure cooling system
has a reservoir filled with year-round
antifreeze coolant. The reservoir is
filled at the factory.
Check the antifreeze protection and
coolant level at least once a year, atthe beginning of the winter season
and before traveling to a colder cli-
mate.Checking the Coolant Level
Check the condition and connections of all cooling system hoses and
heater hoses. Replace any swollen
or deteriorated hoses.
The coolant level should be filled
between the MAX and the MIN
marks on the rear side of the coolant
reservoir when the parts in the fuel
cell power module compartment iscool.
If the coolant level is low, add enough
distilled (deionized) water to bring
the level to the MAX mark, but do not
overfill. If frequent additions are
required, you see an authorized
HYUNDAI dealer for a cooling sys-tem inspection.
Recommended coolant
When adding coolant, use only
distilled (deionized) water for your
vehicle and never mix hard water in
the coolant filled at the factory.
An improper coolant mixture can result in severe malfunction or
electric devices damage.
Do not use alcohol or methanol coolant or mix them with the spec-ified coolant.
Do not use a solution that contains more than 60% antifreeze or less
than 35% antifreeze, which would
reduce the effectiveness of thesolution.
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