2020 TOYOTA MIRAI fuel pump

882. Fuel cell vehicle
MIRAI_OM_USA_OM62073U
■Sounds unique to the fuel cell vehicle
Due to the design of your fuel cell vehicle, there are various relays, valves
and pumps which under normal driving conditions will produce so unds. This
is a normal characteristic of the vehicle and does not indicate a malfunction.
Furthermore, way of hearing may differ based on usage environme nt or con-
dition.
Noticeable soundsSource of the sounds
Clunking, clicking and clack-
ingOperation of relays and hydrogen tank
valves
Sounds may come from under the floor or
behind the rear seats.
(Sounds may be heard when starting the
fuel cell system.)
KnockingThe parking lock is engaged
Sounds may come from the motor
compartment.
(Sounds may be heard when press the P
position switch or stopping the fuel cell
system.)
Whooshing, squealingGas is flowing through the nozzle and
valvesSounds may come from behind the rear
seats, or from the dispenser hose/nozzle.
(Sounds may be heard when filling the
fuel.)
• High pitch sound
• Gurgle sound
• Pulsing soundOperation of the pumpsSounds may come from the motor com-
partment or under the front seats.
(In particular, sounds may be heard when
starting the fuel cell system, accelerating
from a stop, or press the H
2O switch. The
sound may be louder when in Br mode or
when the vehicle decelerates during
dynamic radar cruise control.)
Humming soundOperation of the pumps are speeding up
Sounds may come from the motor com-
partment or under the front seats.
(In particular, sounds may be heard when
accelerating or decelerating.)
Whooshing sound Operation of the hydrogen injectorSounds may come from under the front
seats or behind the rear seats.
(In particular, sounds may be heard when
starting the fuel cell system, driving at low
speeds, or charging the traction battery.)

2125-3. Operating the lights and wipers
MIRAI_OM_USA_OM62073U
NOTICE
■When the windshield is dry
Do not use the wipers, as they may damage the windshield.
■ When the washer fluid tank is empty
Do not operate the switch continually as the washer fluid pump may over-
heat.
■ When a nozzle becomes blocked
In this case, contact your Toyota dealer.
Do not try to clear it with a pin or other object. The nozzle w ill be damaged.
■ To prevent 12-volt b attery discharge
Do not leave the wipers on longer than necessary when the fuel cell system
is off.

3717-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62073U
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Maintenance and care
■If the inverter coolant level drops within a short time of repl enishing
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 extremely dirty or you are not sure of
their condition, have your vehic le inspected by your Toyota dea ler.
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 straight antifreeze. The cor rect 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 p arts 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 c ause seri-
ous injuries, such as burns.

3737-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62073U
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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. 426)
Washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the fuel cell system is hot or ope rating, as
washer fluid contains alcohol and may catch fire if spilled on the fuel cell
system, etc.
NOTICE
■ Do not use any fluid ot her 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, as well as
damaging the pump leading to problems of the washer fluid not s praying.
■ 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.

4098-1. Essential information
MIRAI_OM_USA_OM62073U
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When trouble arises
If your vehicle has to be stopped in an
emergency
Steadily step on the brake pedal with both feet and firmly depress it.
Do not pump the brake pedal repeatedly as this will increase th e effort
required to slow the vehicle.
Shift the shift position to N.
If the shift positi on is shifted to N
After slowing down, stop the vehi cle in a safe place by the road.
Stop the fuel cell system.
If the shift position c annot be shifted to N
Keep depressing the brake pedal with both feet to reduce vehicl e
speed as much as possible.
To stop the fuel cell system,
press and hold the power
switch for 2 consecutive sec-
onds or more, or press it briefly
3 times or more in succession.
Stop the vehicle in a s afe place by the road.
Only in an emergency, such as if it becomes impossible to stop
the vehicle in the normal way, st op the vehicle using the follow-
ing procedure:
1
2
3
4
3
Press and hold for 2 seconds or more,
or press briefly 3 times or more
Q
WARNING
■ If the fuel cell system has to be turned off while driving
Power assist for the steering wheel will be lost, making the steering wheel
heavier to turn. Decelerate as much as possible before turning off the fuel
cell system.
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