maintenance HYUNDAI NEXO 2021 User Guide

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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
OFE078001
The actual fuel cell power module compartment in the vehicle may differ from the illus-
tration.

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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

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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.
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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, level
road.
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

7-7
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Maintenance
At least once a year:
Clean body and door drain holes.
Lubricate door hinges and hoodhinges.
Lubricate door and hood locks and latches.
Lubricate door rubber weather strips.
Lubricate door checker.
Check the air conditioning system.
Inspect and lubricate reduction gear linkage and controls.
Check the brake fluid level.
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Follow Normal Maintenance Schedule if the vehicle is usually operated where
none of the following conditions apply. If any of the following conditions apply,
you must follow the Maintenance Under Severe Usage Conditions.
Repeated driving short distance of less than 8 km (5 miles) in normal tem-
perature or less than 16 km (10 miles) in freezing temperature
Low speed driving for long distances
Driving on rough, dusty, muddy, unpaved, graveled or salt-spread roads
Driving in areas using salt or other corrosive materials or in very cold weather
Driving in heavy dust condition
Driving in heavy traffic area
Driving on uphill, downhill, or mountain road repeatedly
Towing a trailer or using a camper, or roof rack
Driving as a patrol car, taxi, other commercial use of vehicle towing
Driving over 170 km/h (106 miles/h)
Frequently driving in stop-and-go condition
If your vehicle is operated under the above conditions, you should inspect, replace or refill more frequently than the following Normal MaintenanceSchedule. After the periods or distance shown in the chart, continue to followthe prescribed maintenance intervals.

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

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Maintenance
Normal Maintenance Schedule (Cont.)
I : Inspect and if necessary, adjust, correct, clean or replace.
R : Replace
Months1224364860728496108120132144156168180
Miles×1,00061218243036424854606672788490
Km×1,000102030405060708090100110120130140150
Parking brakeIIIIIIIIIIIIIII
Steering gear rack, linkage and
bootsIIIIIIIIIIIIIII
Tire (pressure & tread wear)IIIIIIIIIIIIIII
Battery conditionIIIIIIIIIIIIIII
Brake fluidIIIIIII
Climate control air filterRRRRRRRRRRRRRRR
Maintenance Intervals
Maintenance
Item

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

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MaintenanceSevere driving conditions
A - Repeatedly driving short distances of less than 5 miles (8 km) in normal temperature or less than 10 miles (16 km)
in freezing temperature
B - Extensive low speed driving for long distances
C - Driving on rough, dusty, muddy, unpaved, graveled or salt- spread roads
D - Driving in areas using salt or other corrosive materials or in very cold weather E - Driving in sandy areas
F - Driving in heavy traffic area over 90°F (32°C)
G- Driving on uphill, downhill, or mountain road
H - Towing a Trailer, or using a camper, or roof rack
I - Driving as a patrol car, taxi, other commercial use or vehicle
towing
J - Driving over 106 mph (170 km/h)
K - Frequently driving in stop-and-go conditions
Maintenance itemMaintenance operationMaintenance intervalsDriving condition
Driveshaft and bootsIInspect more frequently
depending on the conditionC, D, E, F, G, H, I, J
Front suspension ball jointsIInspect more frequently
depending on the conditionC, D, E, F, G
Parking brakeIInspect more frequently
depending on the conditionC, D, G, H
Steering gear rack, linkage and bootsIInspect more frequently
depending on the conditionC, D, E, F, G
Climate control air filterRReplace more frequently
depending on the conditionC, E

7-12
Maintenance
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Cooling System
Check cooling system components,
such as radiator, coolant reservoir,
hoses and connections for leakage
and damage. Replace any damaged
parts.
Coolant
The coolant should be changed at
the intervals specified in the mainte-
nance schedule.
Reduction Gear Fluid
Inspect the reduction gear fluid
according to the maintenance sched-
ule.
Brake Hoses and Lines
Visually check for proper installation,
chafing, cracks, deterioration and
any leakage. Replace any deteriorat-
ed or damaged parts immediately.
Brake Fluid
Check brake fluid level in the brake
fluid reservoir. The level should be
between the MIN and the MAX
marks on the side of the reservoir.
Use only hydraulic brake fluid con-
forming to DOT 3 or DOT 4 specifi-
cation.
Brake Discs, Pads, Calipers
and Rotors
Check the pads for excessive wear,
discs for run out and wear, and
calipers for fluid leakage.
Suspension Mounting Bolts
Check the suspension connections
for looseness or damage. Retighten
to the specified torque.
Steering Gear Box, Linkage &
Boots/Lower Arm Ball Joint
With the vehicle stopped and the
vehicle off, check for excessive free-
play in the steering wheel. Check the
linkage for bends or damage. Check
the dust boots and ball joints for
deterioration, cracks, or damage.
Replace any damaged parts.
Drive Shafts and Boots
Check the drive shafts, boots and
clamps for cracks, deterioration, or
damage. Replace any damaged
parts and, if necessary, repack the
grease.
Air Conditioning Refrigerant
Check the air conditioning lines and
connections for leakage and dam-
age.