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3778-2. Steps to take in an emergency
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When trouble arises
*: A buzzer sounds the first time a message is shown on the multi-informa-tion display.
■ System warning lights
The master warning light does not come on or flash in the following cases.
Instead, a separate system warning light will come on along with a message
shown on the multi-information display.
●Malfunction of the ABS
The ABS warning light comes on. ( →P. 370)
● Malfunction of the charging system
The charging system warning light comes on. ( →P. 369)
■ If “High FC Temperature Re duced Power” is displayed
Lower the speed while check the safety, and run the vehicle like this for
several minutes.
If the message goes off, the vehicle can be driven as is, since it temporarily
overheated.
This message may be displayed when driving under severe operating con-
ditions.
(For example, when driving up a long steep hill.)
■ If “Maintenance Required for Hybr id Battery Cooling Parts at Your
Dealer” is displayed
The filter may be clogged, or the air intake vent or duct may be blocked. Have
the vehicle inspected by your Toyota dealer.
■ If “Shift to P Before Exiting Vehicle” is displayed
Message is displayed when the driver’s door is opened without turning the
power switch to off with the shift position in any position other than P.
Shift the shift position to P.
■ If “Shift is in N Release Accelerat or Before Shifting” is displayed
Message is displayed when the accelerator pedal has been depressed and
the shift position is in N. Release the accelerator pedal and shift the shift posi-
tion to D or R.
Comes on⎯Does not sound
Indicates a condition, such as mal-
function of electrical components,
their condition, or indicates the
need for maintenance
Flashes⎯Does not sound
Indicates a situation, such as
when an operation has been per-
formed incorrectly, or indicates
how to perform an operation cor-
rectly
System
warning
light
Warning buzzer*Warning
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![TOYOTA MIRAI 2017 1.G Owners Manual 3798-2. Steps to take in an emergency
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When trouble arises
■If “[P] Switch Malfunction When Parking, Apply Parking Brake Securely
then See Owner’s Manual” is displayed
TOYOTA MIRAI 2017 1.G Owners Manual 3798-2. Steps to take in an emergency
MIRAI_OM_USA_OM62023U
8
When trouble arises
■If “[P] Switch Malfunction When Parking, Apply Parking Brake Securely
then See Owner’s Manual” is displayed](/manual-img/14/6553/w960_6553-378.png)
3798-2. Steps to take in an emergency
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When trouble arises
■If “[P] Switch Malfunction When Parking, Apply Parking Brake Securely
then See Owner’s Manual” is displayed
The shift position may not switch to P even though the P position switch is
pressed.
When parking, choose a flat surface and be sure to engage the parking
brake.
Have the vehicle inspected by your Toyota dealer immediately.
■ If “Shift System Malfunction See Owner’s Manual” is displayed
If left as is, the system may not operate properly and an unexpected hazard
or damage may occur.
Have the vehicle inspected by your Toyota dealer immediately.
■ If “Insufficient Aux Battery Charge When Parking, Apply Parking Brake
Securely then See Owner’s Manual” is displayed
●The parking lock mechanism may not operate.
● The power switch may not turn off. In that case, engage the parking brake
and the switch can be turned to off.
● Even after charging the 12-volt battery, the warning message may continue
to be displayed until the shift position is shifted from P to a position other
than P.
● The fuel cell system may not be able to be started.
When parking, choose a flat surface and be sure to engage the parking
brake.
Have the 12-volt battery charged or replaced.
■ If “Insufficient Aux Battery Charge Shift is Unavailable See Owner’s
Manual” is displayed
Due to the voltage of the 12-volt battery being in a declined condition, when
trying to shift the shift position the warning message is displayed.
Have the 12-volt battery charged or replaced.
■ If “Shifting Temporarily Unavailable Wait a Moment and Try Again” is
displayed
A warning message is displayed when the shift lever and P position switch
are repeatedly operated over a short period of time.
Shift the shift position after waiting for short amount of time.
■ If “Shifting to [Br] Mode Unavailable Shift to [D] once, then Shift to [Br]”
is displayed
When the shift position is in P or N, a warning message is displayed when try-
ing to shift to Br mode.
Shift to Br mode after the shift position had been set to D.
■ If “Shifted to [N] Position Shift to [D] once, then Shift to [Br]” is dis-
played
When the shift position is in R, a warning message is displayed when trying to
shift to Br mode.
The shift position is changed to N.
Shift to Br Mode after the shift position has been set to D.
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3968-2. Steps to take in an emergency
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If the fuel cell system will not start
One of the following may be the cause of the problem:
●The electronic key may not be functioning properly. ( →P. 398)
● There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
● The fuel door may be open. ( →P. 201)
● There may be a malfunction in the immobilizer system.
( → P. 72)
● There may be a malfunction in the shift control system.
* (→ P. 378)
● The fuel cell system may be malf unctioning due to an electrical
problem such as electronic key ba ttery depletion or a blown fuse.
However, depending on the type of malfunction, an interim mea-
sure is available to start the fuel cell system. ( →P. 177, 397)
● The electronic key may be in battery-saving mode. ( →P. 133)
*: It may not be possible to shift the shift position from P to another position.
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. ( →P. 401)
● The 12-volt battery terminal connections may be loose or corroded.
(→ P. 328)
Reasons for the fuel cell system not starting vary depending on
the situation. Check the follo wing and perform the appropriate
procedure:
The fuel cell system will not start even though the correct start-
ing procedure is being followed. ( →P. 172)
The interior lights and headlights are dim, or the horn does not
sound or sounds at a low volume.
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3978-2. Steps to take in an emergency
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When trouble arises
One of the following may be the cause of the problem:
●The 12-volt battery may be discharged. ( →P. 401)
● One or both of the 12-volt batter y terminals may be disconnected.
Contact your Toyota dealer if the problem cannot be repaired, or if repair
procedures are unknown.
When the fuel cell system does not start, the following steps can be
used as an interim measure to star t the fuel cell system if the power
switch is functioning normally.
Do not use this starting procedure except in case of emergency.
Set the parking brake.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for about 15 seconds while
depressing the brake pedal firmly.
Even if the fuel cell system can be started using the above steps, the
system may be malfunctioning. Have the vehicle inspected by your
Toyota dealer.
The interior lights and headlight s do not turn on, or the horn
does not sound.
Emergency start function
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Page 398 of 464
3988-2. Steps to take in an emergency
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If the electronic key does not operate
properly
■Doors
Use the mechanical key
(→ P. 117) in order to perform
the following operations
(driver’s door only):
Locks all doors
Unlocks the door
Turning the key rearward
unlocks the driver’s door. Turn-
ing the key once again unlocks
the other doors.
■
Tr u n k
Turn the mechanical key clock-
wise to open.
If communication between the electronic key and vehicle is
interrupted ( →P. 134) or the electronic key cannot be used
because the battery is depleted, the smart key system and wire-
less remote control cannot be used. In such cases, the doors
can be opened and the fuel cell system can be started by follow-
ing the procedure below.
Locking and unlocking the doors
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4008-2. Steps to take in an emergency
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■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 recommended that the
electronic key battery be replaced immediately when the battery is depleted.
(→P. 353)
■ Alarm
Using the mechanical key to lock the doors will not set the alarm system.
If a door is unlocked using the mechanical key when the alarm system is set,
the alarm may be triggered. ( →P. 75)
■ 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. 436)
● Check if battery-saving mode is set. If it is set, cancel the function.
(→P. 133)
■ Changing power switch modes
Release the brake pedal and press the power switch in step above.
The fuel cell system does not start and modes will be changed each time the
switch is pressed. (→P. 174)
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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4018-2. Steps to take in an emergency
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When trouble arises
If the 12-volt battery is discharged
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your vehicle by following the
steps below.
Open the hood ( →P. 320) and
fuse box cover.
Open the exclusive jump start-
ing terminal cover.
Remove the motor cover.
The following procedures may be used to start the fuel cell sys-
tem if the 12-volt battery is discharged.
You can also call your Toyota de aler or a qualified repair shop.
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4028-2. Steps to take in an emergency
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Connect the jumper cables according to the following procedure:Connect a positive jumper cabl e clamp to the exclusive jump
starting terminal on your vehicle.
Connect the clamp on the other e nd of the positive cable to the
positive (+) battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery termi-
nal on the second vehicle.
Connect the clamp at the other end of the negative cable to a
solid, stationary, unpainted metallic point away from the exclusive
jump starting terminal and any moving parts, as shown in the
illustration.
Start the engine of the second v ehicle. Increase the engine speed
slightly and maintain at that level for approximately 5 minutes to
recharge the 12-volt battery of your vehicle.
Maintain the engine speed of the second vehicle and start the fuel
cell system of your vehicle by turn ing the power switch to ON mode.
Make sure the “READY” indicato r comes on. If the indicator does
not come on, contact your Toyota dealer.
Once the fuel cell system has started, remove the jumper cables in
the exact reverse order from which they were connected.4
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