2017 TOYOTA MIRAI coolant level

993. Instrument cluster
3
Instrument cluster
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Warning lights inform the driver of malfunctions in the indicated vehi-
cle’s systems.
Warning lights
*1
Hydrogen leak warning
light ( →P. 369)*1
Slip indicator ( →P. 370)
*1
Brake system warning
light (→P. 369)Parking brake warning
light (→P. 371)
*1
Charging system
warning light ( →P. 369)Open door warning light
(→P. 371)
*1High coolant
temperature warning
light ( →P. 369)Low fuel level warning
light (→P. 371)
*1
Brake system warning
light (→P. 369)Driver’s and front
passenger’s seat belt
reminder light ( →P. 3 7 1 )
*1
SRS warning light
(→P. 370)*1
Master warning light
(→P. 371)
*1
ABS warning light
(→P. 370)*1
Tire pressure warning
light ( →P. 371)
*1
(Red/
Ye l l o w )
Electric power steering
system warning light
( →P. 370)*3Brake Override System/
Drive-Start Control
warning light ( →P. 372)
*1, 2
PCS warning light
(→P. 370)

3157-2. Maintenance
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7
Maintenance and care
General maintenance
Listed below are the general maintenance items that should be
performed at the intervals specified in the “Owner’s Warranty
Information Booklet” or “Owner’s Manual Supplement/Sched-
uled Maintenance Guide”. It is recommended that any problem
you notice should be brought to the attention of your Toyota
dealer or qualified service shop for advice.
Motor compartment
ItemsCheck points
Brake fluidIs the brake fluid at the correct
level? ( →P. 326)
CoolantIs the coolant at the correct level?
(→P. 324)
Radiator/condenser
The radiator and condenser should
be free from foreign objects.
(→P. 325)
Washer fluidIs there sufficient washer fluid?
(→P. 327)
Tr u nk
ItemsCheck points
12-volt battery Check the connections. (→P. 328)

3187-3. Do-it-yourself maintenance
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Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the
correct procedure as given in these sections.
ItemsParts and tools
12-volt battery
condition
(→ P. 328)•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
(→ P. 326)• FMVSS No.116 DOT 3 or SAE J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Inverter coolant
level ( →P. 324)
• “Toyota Super Long Life Coolant” or a similar high
quality ethylene glycol-based non-silicate, non-
amine, non-nitrite and non-borate coolant with long-
life hybrid organic acid technology.
“Toyota Super Long Life Coolant” is pre-mixed with
50% coolant and 50% deionized water.
• Funnel (used only for adding coolant)
Fuses ( →P. 355)• Fuse with same amperage rating as original
Light bulbs
(→ P. 358)⎯
Radiator and con-
denser (
→P. 325)⎯
Tire inflation
pressure
(→ P. 346)• Tire pressure gauge
• Compressed air source
Washer fluid
(→ P. 327)• Water or washer fluid containing antifreeze (for win-
ter use)
• Funnel (used only for adding water or washer fluid)

3247-3. Do-it-yourself maintenance
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The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the fuel cell system is cold.“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, contact your Toyota
dealer.
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the fuel cell system is cold.Inverter coolant reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■Inverter coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene
glycol based non-silicate, non-amine, non-nitrite, and non-borate coolant with
long-life hybrid organic acid technology.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 °F [-35° C])
For more details about inverter coolant, contact your Toyota dealer.
Fuel cell stack coolant
NOTICE
■ Fuel cell stack coolant
An exclusive coolant for the fuel cell system is filled in the fuel cell stack
coolant reservoir. Do not use any substitute. It may damage your vehicle.
Inverter coolant

3257-3. Do-it-yourself maintenance
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7
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.

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

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 temperature 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.

4088-2. Steps to take in an emergency
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The fuel cell stack coolant level
is satisfactory if it is between
the “FULL” and “LOW” lines on
the reservoir.
Fuel cell stack coolant reser-
voir
“FULL” line
“LOW” line
If the amount of fuel cell stack coolant is low: Immediately contact your Toyota dealer.
If the amount of fuel cell stack coolant is not low: Have the vehicle inspected at the nearest Toyota dealer.
Even if the fuel cell stack cool-
ant is low, do not refill it.4