2021 HONDA CLARITY FUEL CELL battery

uuWhen Driving uFC System in Extreme Cold-weather Conditions
424
Driving
On cold days, you may get sprayed with ex haust water if standing behind the vehicle
when:
• The FC system is idling until the READY indicator comes on at power system
start-up.
• The FC system is in the shutdown proces s after it was stopped before warm-up is
completed.
High Voltage battery is warmed up using the air inside the vehicle. If the air
conditioner is not used or a window is open, it may take time to complete warm-up.
As a result, the power output may be limited or the READY indicator may take
longer than usual to turn on.
When the power system is turned on in ex tremely cold temperatures (–4°F [–20°C]),
its standby operation noise may become l ouder than in normal low temperatures.1FC System in Extreme Cold-weather Conditions
It may take a longer time to start in very cold
conditions or may not start at all until temperatures
rise.
If the temperature of the fuel cell or the High Voltage
battery drops below –4°F (– 20°C), the fuel cells will
not operate and, as a result, the vehicle will not start.
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427Continued
Driving
Braking
Brake System
Use the parking brake to keep the vehicle stationary when parked. When the
parking brake is applied, you can manu ally or automatically release it.
■To apply
The electric parking brake can be applied any
time the vehicle has battery, no matter which
position the power mode is in.
Pull the electric parking brake switch up gently
and securely. u The parking brake and brake system
indicator (red) comes on.
■Parking Brake1Brake System
When you depress the brak e pedal, you may hear a
whirring sound from the motor compartment. This is
because the brake system is in operation, and it is
normal.
1 Parking Brake
You may hear the electric parking brake system
motor operating from the re ar wheel area when you
apply or release the parki ng brake. This is normal.
The brake pedal may slightly move due to the electric
parking brake system opera tion when you apply or
release the parking br ake. This is normal.
You cannot apply or release the parking brake if the
12-volt battery goes dead. 2 If the 12-Volt Battery Is Dead P. 508
If you pull up and hold the electric parking brake
switch while driving, the brakes on all four
wheels are applied by the VSA ® system until the
vehicle comes to a stop. The electric parking
brake then applies, and the switch should be
released.
Electric Parking
Brake Switch
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uuBraking uBrake System
430
Driving
Your vehicle is equipped with disc brakes at all four wh eels. The brake assist system
increases the stopping force when you depress the brake pedal hard in an
emergency situation. The an ti-lock brake system (ABS) helps you retain steering
control when braking very hard.
2 Brake Assist System P. 434
2 Anti-lock Brake System (ABS) P. 433
■Foot Brake1Foot Brake
Check the brakes after driving through deep water,
or if there is a buildup of road surface water. If
necessary, dry the brakes by lightly depressing the
pedal several times.
If you hear a continuous me tallic friction sound when
applying the brakes, this is caused by the brake wear
indicator rubbing on the brake rotor and indicates
that the brake pads need to be replaced. Have the
vehicle checked by an authorized Honda Clarity Fuel
Cell dealer. If you hear onl y an occasional squeak or
squeal when you initially a pply the brake pedal, this
may be normal and caus ed by high frequency
vibration of the brake pads against the rotating brake
disc.
Constantly using the brake pedal while going down a
long hill builds up heat, which reduces the brake
effectiveness.
To help reduce heat build -up in the brakes when
descending a long slope, use regenerative braking to
slow the vehicle down.
When the high voltage battery has fully recharged,
regenerative braking may not be possible.
2 POWER/CHARGE Gauge P. 119
2 High Voltage Battery Charge Level Gauge
P. 120
Do not rest your foot on the brake pedal while
driving, as it will lightly apply the brakes and cause
them to lose effectiveness over time and reduce pad
life. It will also conf use drivers behind you.
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451
Maintenance
This chapter discusses basic maintenance.
Before Performing MaintenanceInspection and Maintenance ............ 452
Safety When Performing Maintenance ..453
Parts and Fluids Used in Maintenance Service ........................................... 454
Maintenance Minder
TM..................... 455
Maintenance Under the Hood Maintenance Items Under the Hood .. 459
Opening the Hood ........................... 460
Inverter Coolant ............................... 461
Transmission Fluid ............................ 463
Brake Fluid ....................................... 463 Refilling Window Washer Fluid......... 464
Replacing Light Bulbs ....................... 465
Checking and Maintaining Wiper
Blades .......................................... 467
Checking and Maintaining Tires
Checking Tires ................................. 470
Tire and Loading Information Label .. 471
Tire Labeling .................................... 471
DOT Tire Quality Grading (U.S. Vehicles).. 473
Wear Indicators................................ 475
Tire Service Life ................................ 475
Tire and Wheel Replacement............ 476 Tire Rotation .................................... 477
Winter Tires ..................................... 478
12-Volt Battery ................................. 479
Remote Transmitter Care Replacing the Button Battery ........... 481
Climate Control System Maintenance.. 482
CleaningInterior Care .................................... 483
Exterior Care.................................... 485
Accessories and Modifications ........ 489
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453
uuBefore Performing Maintenance uSafety When Performing Maintenance
Maintenance
Safety When Performing Maintenance
Some of the most important safe ty precautions are given here.
However, we cannot warn you of every conceivable hazard that can arise in
performing maintenance. Only you can decide whether you should perform a given
task.
• To reduce the possibility of fire or explos ion, keep cigarettes, sparks, and flames
away from the 12-volt battery, all High Volt age system, and all fuel related parts.
• Never leave rags, towels, or other flammable objects under the hood.
u Heat from the motor or the surrounding parts can ignite them, causing a fire.
• To clean parts, use a co mmercially available degreaser or parts cleaner, not
gasoline.
• Wear eye protection and pr otective clothing when working with the 12-volt
battery or compressed air.
• The vehicle must be in a stationary condition.
u Make sure your vehicle is parked on le vel ground, the parking brake is set, and
the power system is turned off.
• Be aware that hot parts can burn you.
u Make sure to let the power system cool thoroughly before touching vehicle
parts.
• Be aware that moving parts can injure you.
u Do not activate the power system unless instructed to do so.
Keep your hands and limbs away from moving parts.
■Maintenance Safety
■Vehicle Safety
1Safety When Performing Maintenance
3WARNING
Improperly maintaining this vehicle or
failing to correct a pr oblem before driving
can cause a crash in which you can be
seriously hurt or killed.
Always follow the inspection and
maintenance recommendations according
to the schedules in this manual.
3WARNING
Failure to properly follow maintenance
instructions and prec autions can cause you
to be seriously hurt or killed.
Always follow the procedures and
precautions in this manual.
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459
Maintenance
Maintenance Under the Hood
Maintenance Items Under the Hood
Washer Fluid
(Black Cap)
12-Volt BatteryBrake Fluid
(Black Cap)
Inverter Coolant
Expansion Tank
Cap
Inverter Coolant
Reserve Tank
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後３時１５分

479
Maintenance
12-Volt Battery
Checking the 12-Volt Battery
Check the battery condition monthly. Look at
the test indicator window and check the
terminals for corrosion.
The battery condition is monitored by the
sensor on the negative terminal. If there is a
problem with the sensor, the warning
message on the driver information interface
will let you know. Have your vehicle checked
by an authorized Honda Clarity Fuel Cell
dealer.
If your vehicle’s battery is disconnected or goes dead:
• The audio system is disabled.
2 Reactivating the audio system P. 202
•The clock resets.
2 Clock P. 134
112-Volt Battery
WARNING: Battery post, terminals,
and related accessories contain lead
and lead compounds.
Wash your hands after handling.
The test indicator’s color information is on the
battery.
When you find corrosion, cl ean the battery terminals
by applying a baking powder and water solution.
Clean the terminals with a damp towel. Cloth/towel
dry the battery. Coat the terminals with grease to
help prevent future corrosion.
3WARNING
The battery gives off explosive hydrogen
gas during normal operation.
A spark or flame can cause the battery to
explode with enough force to kill or
seriously hurt you.
When conducting any battery
maintenance, wear prot ective clothing and
a face shield, or have a skilled technician do
it.
Test Indicator Window
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480
uu12-Volt Battery uCharging the 12-Volt Battery
Maintenance
Charging the 12-Volt Battery
Disconnect both battery cables to prevent da maging your vehicle’s electrical system.
Always disconnect the negative (–) cable first, and reconnect it last.1 12-Volt Battery
When replacing the battery, the replacement must be
of the same specifications.
Consult an authorized Honda Clarity Fuel Cell dealer
for more information.
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