2021 HYUNDAI NEXO coolant

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Your vehicle at a glance
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1. Brake fluid reservoir ..........................7-19
2. Air cleaner.........................................7-20
3. Fuse box ...........................................7-53
4. Windshield washer fluid reservoir .....7-20
5. Device cooling coolant reservoir .......7-13
6. Device cooling radiator cap ..............7-14
7. Stack cooling coolant reservoir.........7-17
8. Stack cooling radiator cap ................7-17
OFE078001The actual Fuel cell power module compartment in the vehicle may differ from the illustration.

3-60
Convenient features of your vehicle
Power gauge
The power gauge shows the energy
consumption rate of the traction
motor.
CHARGE : It shows the charging
status of the battery when it is
being charged by the regenerative
brakes (decelerating or driving on
a downhill road).
The more electric energy is
charged, the lower the gauge level.
ECO : It shows the energy con-
sumption rate during normal driv-
ing condition. POWER : It shows the energy con-
sumption rate of the vehicle when
driving uphill or accelerating. The
more electric energy is used, the
higher the gauge level.
Fuel cell stack temperature
gauge
This gauge shows the temperature
of the fuel cell stack coolant when
the POWER button is ON.
Do not continue driving with an over-
heated fuel cell stack. If your vehicle
overheats, have the vehicle inspected
by an authorized HYUNDAI dealer.
OFE048102
OFE048103

3-61
Convenient features of your vehicle
3
- Fuel Cell Stack
Overheats
If the gauge pointer moves
beyond the normal range area
toward the "H" position, it indi-
cates overheating that may dam-
age the fuel cell stack.Hydrogen fuel gauge
This gauge indicates the approxi-
mate amount of fuel remaining in the
fuel tank (The fuel tank capacity is
given in chapter 8). The fuel gauge is
supplemented by a low fuel warning
light which will illuminate when the
fuel tank is nearly empty.Information -Hydrogen
Fueling Station
According to the hydrogen fueling sta-
tion condition, the hydrogen fuel may
not filled fully.i
NOTICE
Running Out of Fuel
Running out of fuel can expose
vehicle occupants to danger.
You must stop and obtain addi-
tional fuel as soon as possible
after the warning light comes
on or when the gauge indicator
comes close to the ''E'' (Empty)
level.
WARNING
Radiator Cap
Never remove the radiator cap
when the fuel cell power mod-
ule is hot. Otherwise the fuel
cell stack coolant may be under
pressure and cause severe
burns. Wait until the fuel cell
power module is cool before
adding coolant to the reservoir.
WARNING
OFE048133

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Driving your vehicle
If you believe your brakes may be
wet, apply them lightly while driv-
ing until normal braking operation
returns.
Hydroplaning
If the road is wet enough and you are
going fast enough, your vehicle may
have little or no contact with the road
surface and actually ride on the
water. The best advice is SLOW
DOWN when the road is wet.
The risk of hydroplaning increas-
es as the depth of tire tread
decreases, refer to "Tire Tread" in
chapter 7.
Driving in Flooded Areas
Avoid driving through flooded areas
unless you are sure the water is no
higher than the bottom of the wheel
hub. Drive through any water slowly.
Allow adequate stopping distance
because brake performance may be
reduced.
After driving through water, dry the
brakes by gently applying them sev-
eral times while the vehicle is moving
slowly.
Highway Driving
Tires
Adjust the tire inflation, as specified.
Under-inflation may overheat or
damage the tires.
Do not install worn-out or damaged
tires, which may reduce traction or
fail the braking operation.
Information
Never over-inflate your tires above the
maximum inflation pressure, as speci-
fied on your tires.
Coolant and high voltage bat-
tery
Be sure to check both the coolant
level and the high voltage battery
level before driving.
i

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Driving your vehicle
When using tire chains:
Wrong size chains or improperly
installed chains can damage
your vehicle's brake lines, sus-
pension, body and wheels.
Use SAE "S" class or wire
chains.
If you hear noise caused by
chains contacting the body,
retighten the chain to prevent
contact with the vehicle body.
To prevent body damage,
retighten the chains after driving
0.3~0.6 miles (0.5~1.0 km).
Do not use tire chains on vehi-
cles equipped with aluminum
wheels. If unavoidable, use a
wire type chain.
Use wire chains less than 0.47 in
(12 mm) thick to prevent damage
to the chain's connection.
Winter Precautions
Use high quality ethylene glycol
coolant
Your vehicle is delivered with high
quality ethylene glycol coolant in the
cooling system. It is the only type of
coolant that should be used because
it helps prevent corrosion in the cool-
ing system, lubricates the water
pump and prevents freezing. Be sure
to replace or replenish your coolant
in accordance with the maintenance
schedule in chapter 7. Before winter,
have your coolant tested to assure
that its freezing point is sufficient for
the temperatures anticipated during
the winter.
Use approved window washer
anti-freeze in system
To keep the water in the window
washer system from freezing, add an
approved window washer anti-freeze
solution in accordance with instruc-
tions on the container. Window wash-
er anti-freeze is available from an
authorized HYUNDAI dealer and
most auto parts outlets. Do not use
coolant or other types of anti-freeze
as these may damage the paint fin-
ish.
Do not let your parking brake
freeze
Under some conditions your parking
brake can freeze in the engaged
position. This is most likely to happen
when there is an accumulation of
snow or ice around or near the rear
brakes or if the brakes are wet. If
there is a risk the parking brake may
freeze, apply it only temporarily while
you shift to P (Park) and block the
rear wheels so the car cannot roll.
Then release the parking brake.
NOTICE

6-9
What to do in an emergency
1. Pull off the road and stop as soon
as it is safe to do so.
2. Shift to P (Park) and set the park-
ing brake. If the air conditioning is
on, turn it off.
3. If coolant is running out under the
vehicle or steam is coming out
from the hood, stop the vehicle.
Do not open the hood until the
coolant has stopped running or
the steaming has stopped. If there
is no visible loss of coolant and no
steam, leave the vehicle running
and check to be sure the vehicle
cooling fan is operating. If the fan
is not running, turn the vehicle off.4. Check for coolant leaking from the
radiator, hoses or under the vehi-
cle. (If the air conditioning had
been in use, it is normal for cold
water to be draining from it when
you stop.)
5. If coolant is leaking out, stop the
vehicle immediately and call the
nearest authorized HYUNDAI
dealer for assistance.
I IF
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While the vehicle is
running, keep hands,
clothing and tools
away from the mov-
ing parts such as the
cooling fan to prevent
serious injury.
WARNING
Your vehicle is
equipped with a pres-
surized coolant
reserve tank. NEVER
remove the coolant
reserve tank cap or the radiator
drain plug while the radiator is
HOT. Hot coolant and steam
may blow out under pressure,
causing serious injury.
Turn the vehicle off and wait
until the vehicle cools down.
Use extreme care when remov-
ing the coolant reserve tank
cap. Wrap a towel or thick rag
around it, and turn it counter-
clockwise slowly to release
some of the pressure from the
system. Step back while the
pressure is released.
When you are sure all the pres-
sure has been released, contin-
ue turning the cap counter-
clockwise to remove it.
WARNING

6-10
6. If you cannot find the cause of the
overheating, wait until the radiator
temperature has returned to nor-
mal. Then, if coolant has been
lost, carefully add coolant to the
reservoir to bring the fluid level in
the reservoir up to the halfway
mark.
7. Proceed with caution, keeping
alert for further signs of overheat-
ing. If overheating happens again,
call an authorized HYUNDAI deal-
er for assistance.
What to do in an emergency
Serious loss of coolant indi-
cates a leak in the cooling sys-
tem and should be checked as
soon as possible by an author-
ized HYUNDAI dealer.
CAUTION

7
Maintenance
7
Maintenance
Fuel cell power module compartment.................7-3
Maintenance services ...........................................7-4
Owner'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 .....................................................................7-3\
4
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
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