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Maintenance and care
Your vehicle is equipped with a tire pressure warning system that uses
tire pressure warning valves and tr ansmitters to detect low tire infla-
tion pressure before serious problems arise.
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. ( P. 371)
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pr essure warning system must be
initialized. Have tire pressure warning valves and transmitter ID
codes registered by your Toyota dealer. ( P. 333)
◆Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to register the ID code. Have the ID code
registered by your Toyota dealer.
Tire pressure warning system
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3347-3. Do-it-yourself maintenance
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■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to
expose the fabric, and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size
or location of a cut or other damage
If you are not sure, consult with your Toyota dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not reg-
istered, the tire pressure warning system will not work properly. After driv-
ing for about 20 minutes, the tire pressure warning light blinks for 1
minute and stays on to indicate a system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even
if it has seldom or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation
pressure checks. Make sure to check tire inflation pressure as part of
your routine of daily vehicle checks.
■Maximum load of tire
Check that the maximum load of the re placement tire is greater than 1/2
of the Gross Axle Weight Ratings (GAWR) of either the front axle or the
rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. ( P. 422)
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3577-3. Do-it-yourself maintenance
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Maintenance and care
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may
need replacement. ( P. 358)
● If the replaced fuse blows again, have the vehicle inspected by your Toyota
dealer.
■ If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness from damage.
WARNING
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or
injury.
●Never use a fuse of a higher amperage rating than that indicated, or use\
any other object in place of a fuse.
● Always use a genuine Toyota fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
● Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your
Toyota dealer as soon as possible.
Page 358 of 464
3587-3. Do-it-yourself maintenance
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Light bulbs
■LED light bulbs
The following lights consist of a number of LEDs. If any of the LEDs burn out,
take your vehicle to your Toyota dealer to have the light replaced.
●Headlight low beams
● Headlight high beams
● Parking lights and daytime running lights
● Front side marker lights
● Front turn signal lights
● Side turn signal lights
● Tail lights
● Stop lights
● Rear side marker lights
● Rear turn signal lights
● High mounted stop lights
● License plate lights
● Back-up lights
■ Condensation build-up on the inside of the lens
Temporary condensation build-up on the inside of the headlight lens does not
indicate a malfunction.
Contact your Toyota dealer for more information in the following situations:
●Large drops of water have built up on the inside of the lens.
● Water has built up inside the headlight.
If any lights burn out, have it replaced by your Toyota dealer:
WARNING
■ Handling lights
Do not touch the lights while they are on or immediately after they have
been turned off. Doing so may result in burns.
Page 359 of 464
359
8When trouble arises
MIRAI_OM_USA_OM62004U8-1. 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
Page 368 of 464
3688-2. Steps to take in an emergency
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If you think something is wrong
●Fluid leaks under the vehicle.
(Water dripping from the air co nditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● The high coolant temperature warning light flashes or comes on
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the fuel cell system
● Stumbling or running roughly
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, spon gy feeling, pedal almost touches
the floor
If you notice any of the follow ing symptoms, your vehicle proba-
bly needs adjustment or repair. Contact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
Page 369 of 464
3698-2. Steps to take in an emergency
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8
When trouble arises
If a warning light turns on or a warning
buzzer sounds
Calmly perform the following actions if any of the warning lights
comes on or flashes. If a light comes on or flashes, but then
goes off, this does not necessarily indicate a malfunction in the
system. However, if this continues to occur, have the vehicle
inspected by your Toyota dealer.
Warning light and warning buzzer list
Warning lightWarning light/Details/Actions
Hydrogen leak warning light (warning buzzer) When a hydrogen gas leak is detected, a buzzer sounds,
a light comes on, and a warning message is displayed on
the multi-information display.
P. 8 5
Brake system warning light (warning buzzer)*1
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer. Continuing to drive the vehi-
cle may be dangerous.
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer.
High coolant temperat ure warning light
Indicates that the coolant temperature is abnormal
P. 406
Immediately stop the vehicle in a safe place and con-
tact your Toyota dealer.
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system; or
• The electronically controlled brake system
Have the vehicle inspected by your Toyota dealer
immediately.
Page 370 of 464
3708-2. Steps to take in an emergency
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SRS warning lightIndicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system
Have the vehicle inspected by your Toyota dealer
immediately.
ABS warning light
Indicates a malfunction in:
• The ABS; or
• The brake assist system
Have the vehicle inspected by your Toyota dealer
immediately.
(Red/Yellow)
Electric power steering system warning light (warning
buzzer)
Indicates a malfunction in the EPS (Electric Power Steer-
ing) system
Have the vehicle inspected by your Toyota dealer
immediately.
(Flashes)
PCS warning light
Indicates a malfunction in the pre-collision system
The warning light will operate as follows, even when the
system is not malfunctioning:
• The light will come on when the TRAC and VSC sys- tems are turned off. ( P. 234)
• The light will come on when the pre-collision system is
turned off. (P. 239)
• The light will flash when the system cannot temporarily be used. ( P. 242)
Have the vehicle inspected by your Toyota dealer
immediately.
Slip indicator
Indicates a malfunction in:
• The VSC system;
• The TRAC system; or
• The hill-start assist control system
The light will flash when the ABS, VSC or TRAC
system is
operating.
Have the vehicle inspected by your Toyota dealer
immediately.
Warning lightWarning light/Details/Actions
