2020 HYUNDAI NEXO warning light

H17
Close fuel door before turning
vehicle On
This warning message is displayed
when you turn on the vehicle with
the fuel filler door open. Close the
fuel filler door and turn on the vehicle
again.
Hydrogen tank overfilled due
to hydrogen station error
This warning message is displayed
when the hydrogen tank is over-refu-
eled with the hydrogen due to a prob-
lem of the fueling station.
Turn off the vehicle and then turn on
the vehicle. If the message is dis-
played again, have the vehicle
checked by an authorized HYUNDAI
dealer.Small hydrogen leak possible
This warning message is displayed
when the minor hydrogen leakage is
detected in the vehicle. In this case,
have the vehicle checked by an
authorized HYUNDAI dealer.
If the vehicle has to be stopped due
to the leakage, hydrogen gas leak
warning light (red) will illuminate and
'Hydrogen leak detected. Stop safely
immediately.' message is displayed.
Power limited due to low
hydrogen tank temperature
This warning message is displayed
to protect the battery and fuel cell
system when the temperature of the
hydrogen tanks is low.
If this message is still displayed after
the ambient temperature has
increased enough, have the vehicle
checked by an authorized HYUNDAI
dealer.Hydrogen tank temperature
out of range! Stop safely
immediately
This warning message is displayed
to protect the hydrogen tank system
when the temperature of the hydro-
gen tank is too high or too low.
Turn off the vehicle and stop to let
the temperature of the hydrogen tank
go down.▲ ▲
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If this message is still displayed
after the vehicle is turned off
and stopped for a sufficient
time, we recommend you to
stop driving and have your vehi-
cle immediately inspected by an
authorized HYUNDAI dealer.
WARNING

H18
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Hydrogen leak detected. Stop
safely immediately
This warning message is displayed
and the hydrogen gas leak warning
light (red) illuminates when the
hydrogen leakage is detected in the
vehicle. In this case, we recommend
you to stop driving and stop the vehi-
cle immediately at a safe area. Then
turn off the vehicle and have your
vehicle inspected by an authorized
HYUNDAI dealer.
Check hydrogen leak sensor
This warning message is displayed
and the light showing the malfunction
of the hydrogen leakage detection
sensor illuminates when there is a
malfunction with the hydrogen leak-
age detection sensor. In this case,
have the vehicle checked by an
authorized HYUNDAI dealer.
Refueling…
This warning message is displayed
while refueling the vehicle. Do not
turn on the vehicle and wait until the
refueling is complete.Check fuel door sensor
This warning message is displayed
when there is a malfunction with the
sensor located below the fueling inlet
which is used for communicating
with the fueling station. Check and
remove if there is any foreign sub-
stance around the fueling inlet.
If this message is still displayed after
the foreign substance is removed,
have the vehicle checked by an
authorized HYUNDAI dealer.
Open fuel door after turning
vehicle Off
This warning message is displayed
when you try to open the fuel filler
door while the vehicle is turned on.
Turn of the vehicle and open the fuel
filler door. If the message is still dis-
played after a while, have the vehicle
checked by an authorized HYUNDAI
dealer.Replace hydrogen tank.
Maximum number of refill
cycles exceeded
This warning message is displayed
when the number of times refueling
the vehicle exceeds the predefined
number (4,995 times). The fuel cell
system stops operation for safety
even if the vehicle is refueled enough
and when there is no problem with
the vehicle. In this case, have the
hydrogen storage system replaced
by an authorized HYUNDAI dealer.
Power limited due to fuel cell
system error
This warning message is displayed
when there is a malfunction with the
fuel cell system and the power sup-
ply to the fuel cell system is limited.
If the warning light stays on when in
"Ready ( )" state or while driving
the vehicle, this indicates that the
fuel cell system may have failure. In
this case, have the vehicle checked
by an authorized HYUNDAI dealer.
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H32
CategoryQuestionsAnswers
Vehicle
overview
(10 items)
9. Can driving on test roads or over speed
bumps damage the high voltage battery
and hydrogen tank?
The high voltage battery and hydrogen tank are unlikely to be damaged
under normal driving conditions. However, if the system begins to mal-
function due to a direct and serious vehicular impact, you are informed
of those system errors via warning lights on and the LCD display.

10. A water-like liquid is being discharged
from the muffler and bottom of the vehi-
cle. Is it harmful to humans?
Water or vapor discharged is generated from electrochemical reac-
tions in the fuel cell stack, and is not harmful to humans. However,
liquids generated from the reactions can be somewhat acidic, so DO
NOT touch or ingest the liquid!
Also, the water discharged when parking the vehicle indoor may
make a puddle on the floor. Be careful as such puddle can freeze
and result in accident during winter.
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H33
CategoryQuestionsAnswers
Vehicle
Management
(12 items)
11. Can I wash my FCEV with pressurized
water? What if water flows into the fuel
cell power module compartment?
Every component housed in the fuel cell power module compart-
ment is designed to be waterproof like those found in standard vehi-
cles. Therefore, a short circuit of the FCEV cannot happen while
washing the car. However, your FCEV works by utilizing high-voltage
electric power, so it is recommended that you avoid high-pressure car
washes. If the insulation resistance of the FCEV deteriorates due to
car wash, a High voltage warning light may turn on the cluster.

12. When washing the fuel cell power mod-
ule compartment, is there any potential
risk of electric shock resulting from a
high-voltage short circuit?The FCEV is designed to be a waterproof structure, but please
avoid washing the inside of the compartment if possible. Because
there are many high voltage parts in the power module compart-
ment.
13. Can I wash the bottom of the vehicle? If
yes, what should I be aware of?The FCEV is designed to be a waterproof structure, but please
avoid washing the botttom of the vehicle if possible. Because there
are high voltage cables in the under cover.
14. Can driving with a tire chain affect the
drive motor?Driving with a tire chain causes no direct damage to the drive motor.
15. How should I jump start the vehicle?
Try charging it by pressing the "12V BATT RESET" button first.
Refer to the "If the 12 volt battery is discharged" in this guide book.
It it doesn't work, refer to the "Jump starting" in the Owner's manual
chapter 6.

H35
CategoryQuestionsAnswers
Vehicle
Management
(12 items)
19. What are the do-it-yourself (DIY) main-
tenance items for the FCEV?
DIY Check: Device cooling coolant, Stack cooling coolant, Brake
Fluid, Tire and Wheels
DIY Maintenance: Washer fluid, Air cleaner, Climate control air filter,
Wiper blades, Fuse, Light bulb
20. What should I be aware of when doing
DIY maintenance work?Be careful not to touch the high-voltage cable (orange color),
coolant, and ion filter.
21. Tell me what the potential effects are of
parking long-term in a cold area (-4 °F
(-20 °C)) for the FCEV, and whether or
not the vehicle can startup under such
conditions.In most instances, the vehicle can get startup in cold weather with-
out any problems. However, the vehicle may not start if it is parked
with the power off for over a week in cold temperatures. In this case,
If you will not be turning on the vehicle for more than a week in cold
weather, it is recommended that you park the vehicle inside a build-
ing, if possible.
22. What parts must I not touch with
hands? For example, high-voltage
cable, ion filter, etc.?
High-voltage cable (orange color), ion filter, parts with a high voltage
warning sticker.
Also, never touch the hydrogen storage system under the liftgate,
the hydrogen supply pipe under the vehicle and the hydrogen supply
system components on the right side (based on the driver’s position)
of the hood.

H36
CategoryQuestionsAnswers
Cluster/
Warning Lamp
(9 items)
23. What shall I do if the hydrogen gas leak
warning light turns on on the cluster?
(Red)If the hydrogen gas leak warning light turns on during "READY" sta-
tus or in driving mode, this indicates a hydrogen gas leak inside the
vehicle. DO NOT lose your composure. Park your vehicle and turn
OFF the vehicle. Then, we recommend that you contact an author-
ized HYUNDAI dealer for service.
24. Can I keep driving the vehicle even if
the hydrogen gas leak warning light
turns on on the cluster?
(Red)The fuel cell stops working if hydrogen is no longer available. However,
the FCEV can run for an additional distance (About 2 miles (3 km)) in
EV mode where the vehicle runs only on battery power. Mileage in EV
mode can vary depending on the "state of charge" (SOC) of the high
voltage battery, so move your vehicle to the nearest shoulder on the
road. Then, we recommend that you contact an authorized HYUNDAI
dealer for service.
25. While driving to a service center after
the hydrogen gas leak warning light
turns on on the cluster, is it possible
that the vehicle catch fire if there is
something nearby to ignite the leaking
gas (cigarette butt, etc.)?
(Red)
As soon as the hydrogen gas leak warning light appears, the fuel
cell operation is disabled immediately to cut the supply of hydrogen.
This prevents the possibility of a fire occurring.
26. What should I do if a power down warn-
ing light turns on?If the power down warning light turns on during "READY" status or
in driving mode, power supply to the fuel cell system is cut off. If the
warning light turns on repeatedly when restarting the vehicle after
parking your car on the safe place, we recommend that you contact
an authorized HYUNDAI dealer for service.
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H37
CategoryQuestionsAnswers
Cluster/
Warning Lamp
(9 items)
27. What should I do if the service warning
light turns on?If the service warning light turns on during "READY" status or in
driving mode, it may indicate a malfunction in operation with any fuel
cell system. We recommend that you contact an authorized
HYUNDAI dealer for service.
28. What should I do if the master warning
light turns on?If the service warning light turns on when there is a malfuction in
operation in any of the vehicle systems. Please look at the LCD dis-
play for details and we recommend that you contact an authorized
HYUNDAI dealer for service if needed.
29. How much farther (roughly) can I drive
my FCEV when the fuel warning light
turns on? (Remaining mileage)You can continue driving for an additional 40~55 miles (70~90 km).
It may depend on driving mode.
30. When restarting the vehicle, the " "
indicator turns on on the cluster. What
does this mean?It means that the fuel cell system is working in good order and your
car is ready to drive.
31. Why does the vehicle’s hydrogen tank
have a life expectancy?
The hydrogen tank is frequently refueled with the high pressure
hydrogen gas and the number of times refueling the vehicle is limit-
ed to 5,000 times (or 15 years). The hydrogen storage system
counts the number of times the vehicle is refueled and turns on the
warning light when the vehicle is refueled for over 4,995 times.
Every time the vehicle is turned on the warning message "Replace
hydrogen tank. Maximum number of refill cycles exceeded" is dis-
played on the cluster. The vehicle can be driven about 1-3 million
kilometers until the vehicle is refueled 5,000 times, meaning that the
hydrogen tank is used semi-permanently under common driving
condition.

H42
CategoryQuestionsAnswers
Fuel Cell
Stack/High
Voltage
Battery
(4 items)
39. What happens if hydrogen gas leaks
from the fuel cell stack?
(Red)If hydrogen gas leaks beyond what's tolerable from the fuel cell stack,
a hydrogen sensor installed in the system detects the leak and in
response, turns ON the hydrogen gas leak warning light in the cluster.
40. Can the fuel cell stack explode or burn
out due to overheating?The fuel cell stack passed a high temperature test and is deemed
safe, so it is unlikely to explode.
41. Which symptoms occur if the fuel cell
system malfunctions?
If the fuel cell system malfunctions, warning lights specific to the
actual problem appear on the LCD display. When this happens, the
vehicle speed may be limited, or the fuel cell system may shut
down. DO NOT lose your composure if this happens. Park your vehi-
cle and turn OFF the vehicle. Then, we recommend that you contact
an authorized HYUNDAI dealer for service.
42. Is the recharge performance of the high
voltage battery reduced depending on
its length of use? Like any vehicle component, the high voltage battery will decrease
in performance as it ages over time. However, the high voltage bat-
tery of the FCEV is durable enough to work at peak performance
beyond the warranty period.
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