Fuel cell HYUNDAI NEXO 2023 Owner's Manual

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.
OFE078003

7-14
Maintenance
For mixing percentage, refer to the
following table:Information
If in doubt about the mix ratio, a 50%
water and 50% antifreeze mix is the
easiest to mix together as it will be the
same quantity of each. It is suitable to
use for most temperature ranges of
-35°C (-31°F) and higher.
i
Ambient
Temperature Mixture Percentage
(volume)
Antifreeze Water
-15°C (5°F) 35 65
-25°C (-13°F) 40 60
-35°C (-31°F) 50 50
-45°C (-49°F) 60 40
Never remove the
radiator cap or the drain plug while the
radiator is hot. Hotcoolant and steam
may blow out under pressure,
causing serious injury.
WARNING
OFE078004 Turn the vehicle off and wait
until the parts in the fuel cell
power module compartment
cools down. Use extreme care
when removing the radiator
cap. Wrap a thick towel around
it, and turn it counterclockwise
slowly to the first stop. Step
back while the pressure is
released from the cooling sys-
tem. When you are sure all thepressure has been released,
press down on the cap, using a
thick towel, and continue turn-
ing counterclockwise to removeit.

7-15
7
MaintenanceThe electric motor for the cooling fan
is controlled by coolant temperature,
refrigerant pressure and vehicle
speed. As the coolant temperature
decreases, the electric motor will
automatically shut off. This is a nor-mal condition.
Changing Coolant
Have coolant changed by an author-
ized HYUNDAI dealer according tothe Maintenance Schedule at the
beginning of this chapter.To prevent damage to parts in the
fuel cell power module compart-
ment, put a thick towel around the
coolant cap before refilling the
coolant to prevent the coolant
from overflowing into parts in the
fuel cell power module compart-ment.
NOTICE
The electric motor for
the cooling fan may
continue to operate
or start up when the
vehicle is not running
and can cause serious injury.
Keep hands, clothing and tools
away from the rotating fan
blades of the cooling fan.
WARNING
Do not use coolant or antifreeze
in the washer fluid reservoir.
Coolant can severely obscure
visibility when sprayed on the
windshield and may cause loss
of vehicle control resulting in anaccident.
Coolant may also cause dam-
age to paint and body trim.
WARNING

7-16
MaintenanceS
S TT AA CCKK CC OO OOLLIINN GG CC OO OOLLAA NN TT
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.
When replacing any part of the cool-
ing system there may be loss of
coolant. In that case, fill with an
exclusive coolant for the fuel cell.When replacing the ion filter car-
tridge, replace the whole stackcoolant.
The coolant level should be filled
between F (MAX) and L (MIN) marks
on the side of the coolant reservoir
when the fuel cell power module iscool. If the stack cooling coolant level is
low, add enough exclusive coolant
for fuel cell stack to provide protec-tion against freezing and corrosion in
the authorized HYUNDAI dealer.
In addition, whenever replacing the
ion filter cartridge, add enough exclu-
sive coolant for fuel cell stack.
OFE078005

Stack cooling coolant
When adding stack coolingcoolant, use only exclusive coolant
for fuel cell stack in authorized
HYUNDAI dealer and never mix
any water or liquid.
An improper coolant mixture can result in severe malfunction or
electric devices damage.
If the vehicle is damaged by adding unspecified liquid except exclusive
coolant for fuel cell stack, it will not
be covered by the warranty.
7-17
7
Maintenance
Never remove the
radiator cap or the drain plug while the
radiator is hot. Hotcoolant and steam
may blow out under pressure,
causing serious injury.
WARNING
OFE078006 Turn the vehicle off and wait
until the parts in the fuel cell
power module compartment
cools down. Use extreme care
when removing the cap. Wrap a
thick towel around it, and turn it
counterclockwise slowly to the
first stop. Step back while the
pressure is released from the
cooling system. When you aresure all the pressure has been
released, press down on the
cap, using a thick towel, and
continue turning counterclock-
wise to remove it.

The electric motor for the cooling fan
is controlled by coolant temperature,
refrigerant pressure and vehicle
speed. As the coolant temperature
decreases, the electric motor will
automatically shut off. This is a nor-mal condition.
Changing Coolant
For the fuel cell stack, an exclusive
coolant must be used . When chang-
ing the fuel cell stack coolant, werecommend that coolant be changed
by an authorized HYUNDAI dealeraccording to the MaintenanceSchedule at the beginning of this
chapter.To prevent damage to parts in the
fuel cell power module compart-
ment, put a thick towel around the
coolant cap before refilling the
coolant to prevent the coolant
from overflowing into parts in the
fuel cell power module compart-ment.
NOTICE
7-18
Maintenance
The electric motor for
the cooling fan may
continue to operate
or start up when the
vehicle is not running
and can cause serious injury.
Keep hands, clothing and tools
away from the rotating fan
blades of the cooling fan.
WARNING
Do not use coolant or antifreeze
in the washer fluid reservoir.
Coolant can severely obscure
visibility when sprayed on the
windshield and may cause loss
of vehicle control resulting in anaccident.
Coolant may also cause dam-
age to paint and body trim.
WARNING
Do not mix-up the caps of
device cooling coolant and
stack cooling coolant because
the fluid material is different. If
the cap is mixed, the fuel cell
system may be damage.
We recommend that you con-
sult an authorized HYUNDAI
dealer.
CAUTION

7-45
7
Maintenance
FFUU SSEE SS
A vehicle's electrical system is pro-
tected from electrical overload dam-
age by fuses.
This vehicle has 2 (or 3) fuse panels,
one located in the driver's side panel
bolster, the other in the fuel cell
power module compartment near the
battery. If any of your vehicle’s lights, acces-
sories, or controls do not work, check
the appropriate circuit fuse. If a fuse
has blown, the element inside the
fuse will be melted or broken.
If the electrical system does not
work, first check the driver's side
fuse panel. Before replacing a blown
fuse, turn the vehicle and all switch-
es off, and then disconnect the neg-
ative battery cable. Always replace a
blown fuse with one of the same rat-ing.
If the replacement fuse blows, this
indicates an electrical problem. Avoid
using the system involved and imme-
diately consult an authorized
HYUNDAI dealer.
Information
Three kinds of fuses are used: blade
type for lower amperage rating, car-
tridge type, and multi fuse for higher
amperage ratings.
i
NEVER replace a fuse with any-
thing but another fuse of thesame rating.
A higher capacity fuse could
cause damage and possibly
cause a fire.
Do not install a wire or alu-
minum foil instead of the
proper fuse - even as a tem-
porary repair. It may cause
extensive wiring damage and
possibly a fire.
WARNING
Normal
■
Blade type
■ Cartridge type Blown
Normal Blown
OAEE076008
Normal
Blown
■ Multi fuse

7-46
Maintenance
Do not use a screwdriver or any
other metal object to remove
fuses because it may cause a
short circuit and damage the sys-tem.
Instrument Panel Fuse Replacement
1. Turn the vehicle off.
2. Turn all other switches OFF.
3. Open the fuse panel cover.
4. Refer to the label on the inside ofthe fuse panel cover to locate the suspected fuse location. 5. Pull the suspected fuse straight
out. Use the removal tool provided
in the fuel cell power module com-
partment fuse panel.
6. Check the removed fuse; replace it if it is blown. Spare fuses are pro-
vided in the instrument panel fuse
panels (or in the fuel cell power
module compartment fuse panel).
7. Push in a new fuse of the same rating, and make sure it fits tightly
in the clips. If it fits loosely, consult
an authorized HYUNDAI dealer.
NOTICE
OFE078018
OFE078017

7-47
7
Maintenance
In an emergency, if you do not have
a spare fuse, use a fuse of the same
rating from a circuit you may not
need for operating the vehicle.
If the headlamps or other electrical
components do not work and the
fuses are OK, check the fuse panel
in the fuel cell power module com-
partment. If a fuse is blown, it must
be replaced with the same rating.Fuel Cell Power Module
Compartment Panel FuseReplacement
Blade / Cartridge type
1. Turn the vehicle off.
2. Turn all other switches OFF.
3. Remove the fuse panel cover bypressing the tap and pulling up. 4. Check the removed fuse; replace
it if it is blown. To remove or insert
the fuse, use the fuse puller in the
motor compartment fuse panel.
5. Push in a new fuse of the same rating, and make sure it fits tightly
in the clips. If it fits loosely, consult
an authorized HYUNDAI dealer.
OFE078021