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4458-2. Steps to take in an emergency
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When trouble arises
WARNING
■Driving to spread the liquid sealant evenly
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and ca use death
or serious injury.
●Drive the vehicle carefully at a low speed. Be especially caref ul when
turning and cornering.
●If the vehicle does not drive straight or you feel a pull throu gh the
steering wheel, stop the vehi cle and check the following:
• Tire condition. The tire may have separated f rom the wheel.
• Tire inflation pressure. If tire inflation pressure is 19 psi (130 kPa,
1.3 kgf/cm
2 or bar) or less, this may i ndicate severe tire damage.
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4468-2. Steps to take in an emergency
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NOTICE
■When performing an emergency repair
●A tire should only be repaired with the emergency tire puncture repair
kit if the damage is caused by a sharp object such as nail or s crew
passing through the tire tread.
Do not remove the sharp object from the tire. Removing the obje ct may
widen the opening and disenable e mergency repair with the repair kit.
●The repair kit is not waterproof. Make sure that the repair kit is not
exposed to water, such as when it is being used in the rain.
●Do not put the repair kit direct ly onto dusty ground such as sa nd at the
side of the road. If the repair kit vacuums up dust etc., a mal function
may occur.
■Handling the emergency tire puncture repair kit
●The repair kit power source should be 12 V DC suitable for vehi cle
use. Do not connect the repa ir kit to any other source.
●If organic substances such as benzene or gasoline splatters on the
repair kit, the repair kit may deteriorate. Take care not to al low organic
substances to contact it.
●Place the repair kit in a stor age to prevent it from being exposed to dirt
or water.
●Store the repair kit in the assigned place out of reach of chil dren.
●Do not disassemble or modify the repair kit. Do not subject par ts such
as the air pressure indicator to impacts. This may cause a malf unction.
■To avoid damage to the tire pressure warning valves and transmi t-
ters
When a tire is repaired with liqui d sealants, the tire pressure warning
valve and transmitter may not operate properly. If a liquid sea lant is
used, contact your Toyota dealer as soon as possible. After use of liquid
sealant, make sure to replace the tire pressure warning valve a nd trans-
mitter when repairing or replacing the tire. ( P. 379)
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4518-2. Steps to take in an emergency
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When trouble arises
■Stopping the fuel cell system
Shift the shift position to P and press the power switch as you normally do
when stopping the fuel cell system.
■ Replacing the key battery
As the above procedure is a temporary measure, it is recommende d that the
electronic key battery be replaced immediately when the battery is depleted.
( P. 400)
■ Alarm
Using the mechanical key to lock the doors will not set the ala rm system.
If a door is unlocked using the mechanical key when the alarm system is set,
the alarm may be triggered. ( P. 82)
■ When the electronic key does not work properly
●Make sure that the smart key system has not been deactivated in the cus-
tomization setting. If it is off, turn the function on.
(Customizable features P. 486)
● Check if battery-saving mode is set. If it is set, cancel the f unction.
( P. 145)
■ Changing power switch modes
Release the brake pedal and press the power switch in step abo ve.
The fuel cell system does not start and modes will be changed each time the
switch is pressed. ( P. 188)
WARNING
■When using the mechanical key and operating the power windows
Operate the power window after checking to make sure that there is no pos-
sibility of any passenger having any of their body parts caught in the win-
dow.
Also, do not allow children to operate the mechanical key. It is possible for
children and other passengers to get caught in the power window .
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4558-2. Steps to take in an emergency
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When trouble arises
●When the 12-volt battery is reconnected, start the fuel cell sy stem, depress
the brake pedal, and confirm that it is possible to shift into each shift posi-
tion.
● If the battery is removed or the terminals disconnected without operating the
water release function during cold weather, the vehicle may not start due to
the fuel cell system being frozen. To prevent this, operate the water release
function before removing the battery or disconnecting the terminals.
( P. 190)
■ When exchanging the 12-volt battery
Use a Central Degassing type 12-volt battery (Japanese Industri al Stan-
dards). Also, use 12-volt batteries with case sizes similar to one prior the
exchange and an equivalent 20 hour rate capacity (20HR) or grea ter.
• If the sizes differ, the 12-volt battery cannot be properly se cured.
• If the 20 hour rate capacity is low, even if the time period w here the vehicle
is not used is a short time, the 12-volt battery may discharge and fuel cell
system may not be able to start.
For details, consult your Toyota dealer.
WARNING
■ Avoiding 12-volt batte ry fires or explosions
Observe the following precautions to prevent accidentally ignit ing the flam-
mable gas that may be emitted from the 12-volt battery:
● Make sure each jumper cable is connected to the correct terminal and that
it is not unintentionally in contact with any other than the in tended terminal.
● Do not allow the other end of the jumper cable connected to the “+” termi-
nal to come into contact with any other parts or metal surfaces in the area,
such as brackets or unpainted metal.
● Do not allow the + and - clamps of the jumper cables to come in to contact
with each other.
● Do not smoke, use matches, cigarette lighters or allow open fla me near
the 12-volt battery.
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4568-2. Steps to take in an emergency
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WARNING
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic ele ctrolyte,
while related parts contain lead and lead compounds. Observe th e following
precautions when handling the 12-volt battery:
● When working with the 12-volt battery, always wear safety glass es and
take care not to allow any 12-volt battery fluids (acid) to come into contact
with skin, clothing or the vehicle body.
● Do not lean over the 12-volt battery.
● In the event that 12-volt battery fluid comes into contact with the skin or
eyes, immediately wash the affected area with water and seek me dical
attention.
Place a wet sponge or cloth over the affected area until medica l attention
can be received.
● Always wash your hands after handling the 12-volt battery suppo rt, termi-
nals, and other battery-related parts.
● Do not allow children near the 12-volt battery.
■ After recharging the 12-volt battery
Have the 12-volt battery inspected at your Toyota dealer as soo n as possi-
ble.
If the 12-volt battery is deteriorating, continued use may caus e the 12-volt
battery to emit a malodorous gas, which may be detrimental to the health of
passengers.
■ When exchanging the 12-volt battery
After exchanging, securely attach the exhaust hose and exhaust hole plug
to the exhaust hole of the exchanged 12-volt battery. If not pr operly
installed, gases (hydrogen) may leak into the vehicle interior, and there is
the possible danger of the gas igniting and exploding.
■ When replacing the 12-volt battery
P. 376
NOTICE
■To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when chargin g the 12-volt
battery from another vehicle in an emergency. It cannot be used to jump
start another vehicle.
■ When handling jumper cables
When connecting the jumper cables, ensure that they do not beco me entan-
gled in the cooling fans.
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4578-2. Steps to take in an emergency
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When trouble arises
If your vehicle overheats
The following may indicate that your vehicle is overheating.
● The high coolant temperature warning light ( P. 418) comes on
or flashes, or a loss of fuel ce ll system power is experienced. (For
example, the vehicle s peed does not increase.)
● “FC System Overheat Output Power is Limited” ( P. 426) is dis-
played on the multi-in formation display
● Steam comes out from under the hood.
Label
Fuel cell stack coolant
reservoir Inverter coolant reservoir
Page 458 of 528
4588-2. Steps to take in an emergency
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If the high coolant temperature warning light comes on or
flashes
Stop the vehicle in a safe place and turn off the air condition
ing sys-
tem, and then stop t he fuel cell system.
If you see steam or coolant leaks:
Carefully lift the hood after the steam subsides.
If you do not see steam or coolant leaks:
Carefully lift the hood.
After the fuel cell system has
cooled down sufficiently,
inspect the hoses and radiator
core (radiator) for any leaks.
Fuel cell stack coolant sub
radiator
Fuel cell stack coolant radia-
tor
Electric cooling fans
If a large amount of coolant leaks, immediately contact your Toyota
dealer.
NOTICE
Correction procedures
The fuel cell stack coolant is exclusive for
fuel cell stack usage. Damage may occur
when water or any other type of coolant
is used, so never use any other fluid.
If the fuel cell stack coolant is low, imme-
diately contact your Toyota dealer.
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Page 461 of 528

4618-2. Steps to take in an emergency
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When trouble arises
Start the fuel cell system and turn the air conditioning system on
to check that the radiator coo ling fans operate and to check fo r
coolant leaks from t he radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating b y checking
the fan sound and air flow. If it is difficult to check these, turn the air con-
ditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the fuel cell system immed iately and contact your Toyota
dealer.
If the fans are operating:
Have the vehicle inspected at the neare st Toyota dealer.
WARNING
■When inspecting under th e hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
● If steam is seen coming from under the hood, do not open the ho od until
the steam has subsided. The motor compartment may be very hot.
● After the fuel cell system has been turned off, check that the “READY”
indicator is off.
When the fuel cell system is operating, the cooling fans may suddenly
operate even if the fuel cell system stops. Do not touch or app roach rotat-
ing parts such as the fans, which may lead to fingers or clothing (espe-
cially a tie, a scarf or a muffler) getting caught, resulting i n serious injury.
● Do not loosen the coolant reservoir caps or radiator cap, while the fuel cell
system and radiator are hot.
High temperature steam or coolant could spray out.
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