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832. Fuel cell vehicle
2
Fuel cell system
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The fuel cell vehicle has high-voltage components (about 650 V maxi-
mum) such as a fuel cell stack, traction battery, power control unit,
high-voltage cables (which are distinguished from low-voltage cables
by their orange covers), electric motor (traction motor), etc., and high-
temperature parts such as the radiator for cooling. Pay attention to all
warning labels attached to the vehicle.
This diagram is for illustrative purposes only and may differ from the
actual vehicle.
High-voltage and high-temperature components
Warning label
Power control unit
High-voltage cables (orange)
Fuel cell stack
Traction battery
Service plug
Fuel cell converter Electric motor (traction motor)
Air conditioning compressor
Radiator for inverter cooling
Radiator for fuel cell stack
cooling
Auxiliary inverter
Cabin coolant heater1
2
3
4
5
6
7
8
9
10
11
12
13
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872. Fuel cell vehicle
2
Fuel cell system
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Fuel cell stack coolant
●Fuel cell stack coolant uses a specifically-designed fluid with high electrical
insulation properties, in order to safely cool the high-voltage fuel cell stack.
● Never add water or other coolants to the fuel cell stack cooling system, as
they will cause permanent damage.
● Consult your Toyota dealer for replenishing or changing the fuel cell stack
coolant.
■ Ion filter
●An ion filter is installed in the coolant lines for the fuel cell stack, in order to
maintain the normal insulation properties of the coolant.
● It is necessary to periodically change the ion filter. ( P. 378) Contact your
Toyota dealer for this periodic maintenance.
■ Tailpipe
●When the power switch is turned off and the fuel cell system is stopped
(P. 173) after driving, exhaust water is discharged. Be careful when stand-
ing behind the vehicle to avoid dripping or spraying.
● It is possible to manually purge the exhaust. This may be desirable, for
instance, before parking in a garage. This is done by pressing the H
2O
switch. ( P. 173)
● On cold days, water vapor in the exhaust may appear as a white mist emit-
ted from the tailpipe. This is not a malfunction.
● If the tailpipe is blocked, the fuel cell system will stop.
■ Hydrogen detectors
When the power switch is turned to ON mode, the hydrogen detectors are
activated.
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882. Fuel cell vehicle
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Power output restriction
When the power output is restricted, the vehicle may fail to accelerate or even
decelerate, even though the accelerator pedal is depressed. If a safe driving
speed cannot be maintained, stop the vehicle in a safe place away from the
traffic. This may be caused by the following conditions:
●The coolant temperature may be too high. This can be caused by driving
conditions such as repeated sudden acceleration and deceleration, continu-
ous driving on an incline, continuous driving at high altitudes with a high
load, etc. In such situations, the power output restriction indicator (amber) is
displayed on the main display, “High FC Temperature Reduced Power” is
displayed on the multi-information display, and the power output is
restricted. Once the coolant returns to normal temperature, the power out-
put will return to normal. ( P. 377)
● The remaining fuel may be low. After the low fuel warning indicator comes
on, the output power will be gradually restricted in order to extend the possi-
ble driving distance. Once getting to this point, the remaining driving dis-
tance possible is short. Immediately refill the vehicle with hydrogen.
● On cold days, the low fuel warning indicator comes on faster than usual and
the output power is restricted.
■ Vehicle proximity notification system
In the following cases, the vehicle proximity notification system may be diffi-
cult to hear for people around.
●In very noisy areas
● In wind or rain
Also, because the vehicle proximity notification system is located in the front
of the vehicle, it may be more difficult to hear from the rear of the vehicle
compared to the front.
■ Electromagnetic waves (EMF)
●High-voltage parts and cables in fuel cell vehicles have an electromagnetic
shielding configuration, and therefore emit approximately the same amount
of electromagnetic waves as conventional gasoline-powered vehicles or
home electronic appliances.
● Your vehicle may cause sound interference in some third party-produced
radio parts.
■ Traction battery
The traction battery has a limited service life. The lifespan of the traction bat-
tery can change according to driving style and driving conditions.
Page 99 of 464
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)
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1033. Instrument cluster
3
Instrument cluster
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ECO MODE indicator and POWER MODE indicator
Displays the selected driving mode.
(P. 181)
Power restriction indicator
Blue: The fuel cell system output power is restricted, because the
coolant temperature is low.
Amber: The fuel cell system output power is restricted, because the
coolant temperature is high.
Outside temperature
Displays the outside temperature within the range of -40°F (-40°C)
to 122°F (50°C).
Low outside temperature indicator flashes when the ambient temper-
ature is 37°F (3°C) or lower.
Driving range distance
Displays the estimated maximum distance that can be driven with
the quantity of fuel remaining. • This distance is computed based on your average fuel consump-
tion. As a result, the actual distance that can be driven may differ
from that displayed.
• When only a small amount of fuel is added to the hydrogen tanks, the display may not be updated.
Speedometer
Displays the vehicle speed.
Odometer and trip meter
Odometer:
Displays the total distance the vehicle has been driven.
Trip meter:
Displays the distance the vehicle has been driven since the meter
was last reset.
Trip meters “A” and “B” can be used to record and display different
distances independently.
Distance after start:
Displays the distance driven after the fuel cell system was started.
Blank:
A blank is displayed.
2
3
4
5
6
7
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1063. Instrument cluster
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Outside temperature display
●In the following situations, the correct outside temperature may not be dis-
played, or the display may take longer than normal to change.
• When stopped, or driving at low speeds (less than 16 mph [25 km/h])
• When the outside temperature has changed suddenly (at the entrance/
exit of a garage, tunnel, etc.)
● When “--” or “E” is displayed, the system may be malfunctioning.
Take your vehicle to your Toyota dealer.
■ Liquid crystal display
Small spots or light spots may appear on the display. This phenomenon is
characteristic of liquid crystal displays, and there is no problem continuing to
use the display.
■ Customization
The meter display can be customized on the multi-information display.
(Customizable features: P. 439)
NOTICE
■To prevent damage to the fuel cell system and its components
This vehicle is equipped with high coolant temperature warning light
( P. 369), instead of, coolant temperature gauge.
The fuel cell system may be overheating if the high coolant temperature
warning light flashes or comes on. In this case, immediately stop the
vehicle in a safe place, and check the fuel cell system after it has cooled
completely.
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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)
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3187-3. Do-it-yourself maintenance
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Do-it-yourself ser vice 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)