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Maintenance and care
■If the inverter coolant level drops within a short time of replenishing
Visually check the radiators, hoses, inverter coolant reservoir cap, drain cock
and water pump.
If you cannot find a leak, have your Toyota dealer test the cap and check for
leaks in the cooling system.
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is ex tremely dirty or you are not sure of
their condition, have your vehicle inspected by your Toyota dealer.
WARNING
■ When the fuel cell system is hot
Do not remove the coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor stra ight antifreeze. The correct mixture of
water and antifreeze must be used to provide proper lubrication, corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
■ If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
Radiator and condenser
WARNING
■When the fuel cell system is hot
Do not touch the radiator or condenser as they may be hot and cause seri\
-
ous injuries, such as burns.
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Maintenance and care
If none of the washer do not work
or the warning message appears
on the multi-information display,
the washer tank may be empty.
Add washer fluid. (→P. 376)
Washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the fuel cell system is hot or operating, as
washer fluid contains alcohol and may catch fire if spilled on the fuel cell
system, etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■ Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bot-
tle.
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3297-3. Do-it-yourself maintenance
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Maintenance and care
Install the 12-volt battery cover.
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flam-
mable and explosive. Therefore, observe the following precautions before
recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to dis-
connect the ground cable.
● Make sure the power switch on the charger is off when connecting and dis-
connecting the charger cables to the 12-volt battery.
■ After recharging/reconnect ing the 12-volt battery
● Unlocking the doors using the smart key system may not be possible imme-
diately after reconnecting the 12-volt battery. If this happens, use the wire-
less remote control or the mechanical key to lock/unlock the doors.
● Start the fuel cell system with the power switch in ACCESSORY mode. The
fuel cell system may not start with the power switch turned off. However, the
fuel cell system will operate normally from the second attempt.
● The power switch mode is recorded by the vehicle. If the 12-volt battery is
reconnected, the vehicle will return the power switch mode to the status it
was in before the 12-volt battery was disconnected. Make sure to turn off
the power before disconnect the 12-volt battery. Take extra care when con-
necting the 12-volt battery if the power switch mode prior to discharge is
unknown.
● When the 12-volt battery is reconnected, start the fuel cell system, depress
the brake pedal, and confirm that it is possible to shift into each shift posi-
tion.
If the system will not start even after multiple attempts at all methods above,
contact your Toyota dealer.
Installing the 12-volt battery cover
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Maintenance and care
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the fuel cell system is operating.
Also, be sure all accessories are turned off.
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Maintenance and care
Replacing the tire
●Stop the vehicle on a hard, flat surface.
● Set the parking brake.
● Shift the shift position to P.
● Stop the fuel cell system.
When raising your vehicle with a jack, position the jack cor-
rectly. Improper placement may damage your vehicle or cause
injury.
If necessary tire replacement seems difficult to perform, contact
your Toyota dealer.
Before jacking up the vehicle
Location of the tools and jack
Wheel nut wrench
Towing eyelet Jack handle
Jack
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3407-3. Do-it-yourself maintenance
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Remove the luggage mat.
Take out the jack.
WARNING
■Using the tire jack
Observe the following precautions.
Improper use of the tire jack may cause the vehicle to suddenly fall off
the jack, leading to death or serious injury.
●Do not use the tire jack for any purpose other than replacing tires or
installing and removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a tire.
Do not use it on other vehicles, and do not use other tire jacks for
replacing tires on this vehicle.
●Always check that the tire jack is securely set to the jack point.
●Do not put any part of your body under the vehicle while it is supported
by the jack.
●Do not operate the fuel cell system or drive the vehicle while the vehi-
cle is supported by the jack.
●Do not raise the vehicle while someone is inside.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greater than that required to
replace the tire.
●Use a jack stand if it is necessary to get under the vehicle.
●When lowering the vehicle, make sure that there is no-one near the
vehicle. If there are people nearby, warn them vocally before lowering.
Taking out the jack
1
2
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Maintenance and care
Tire valve
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure usi ng the gauge gradations.
If the tire inflation pressure is not at the recommended level, adjust
the pressure.
If you add too much air, press the center of the valve to deflate.
After completing the tire inflation pressure measurement and
adjustment, apply soapy water to the valve and check for leakage.
Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation pressure every two weeks, or at least once
a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the following:
●Reduced fuel economy
●Reduced driving comfort and poor handling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drivetrain
If a tire needs frequent inflating, have it checked by your Toyota dealer.
Inspection and adjustment procedure
1
2
3
4
5
6
Page 359 of 464
359
8When trouble arises
MIRAI_OM_USA_OM62023U8-1. Essential information
Emergency flashers .......... 360
If your vehicle has to be stopped in an
emergency ...................... 361
8-2. Steps to take in an emergency
If your vehicle needs to be towed ......................... 362
If you think something is wrong .............................. 368
If a warning light turns on or a warning buzzer
sounds ............................ 369
If a warning message is displayed......................... 376
If you have a flat tire.......... 381
If the fuel cell system will not start ..................... 396
If the electronic key does not operate properly........ 398
If the 12-volt battery is discharged ................... 401
If your vehicle overheats ........................ 406
If the vehicle becomes stuck ............................... 412