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374 4-3. Do-it-yourself maintenance
■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.
U.S.A.: “Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized water. (Minimum temperature: -31 F [-35 C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized water. (Minimum temperature: -44 F [-42 C])
For more details about coolant, contact your Toyota dealer.
■ If the coolant level drops within a short time of replenishing
Visually check the radiators, hoses, engine/power control unit coolant reser-
voir caps, 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 systems.
CAUTION
■When the hybrid system is hot
Do not remove the engine coolant radiator cap and power control unit cool-
ant reservoir cap.
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.
Page 413 of 563
410 4-3. Do-it-yourself maintenance
25 ECU-B NO.2 7.5 AAir conditioning system, gauge
and meters, occupant classifica-
tion system, tire pressure warning
system, starter system, smart key
system, power door lock system
26 AM2 7.5 A Starter system
27 STRG LOCK 20 A Starter system
28 ABS NO.2 10 A Brake system
29 IGCT-MAIN 30 A IGCT NO.2, IGCT NO.3, IGCT
NO.4, PCU, BATT FAN
30 D/C CUT 30 A DOME, ECU-B NO.1
31 PTC HTR NO.1 30 A PTC heater
32 PTC HTR NO.2 30 A PTC heater
33 FAN 30 A Electric cooling fan
34 PTC HTR NO.3 30 A PTC heater
35 DEF 30 A MIR HTR, rear window defogger
36 DEICER 20 A No circuit
37 BATT FAN 10 A Battery cooling fan
38 IGCT NO.2 10 A Hybrid system
39 IGCT NO.4 10 A Hybrid system
40 PCU 10 A Hybrid system
41 IGCT NO.3 10 A Hybrid system
42 MIR HTR 10 A Outside rear view mirror defoggers
FuseAmpereCircuit
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486 5-2. Steps to take in an emergency
CAUTION
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic electrolyte,
while related parts contain lead and lead compounds. Observe the following
precautions when handling the 12-volt battery:
●When working with the 12-volt battery, always wear safety glasses and
take care not to allow any battery fluids (acid) to come into contact with
skin, clothing or the vehicle body.
● Do not lean over the 12-volt battery.
● In the event that battery fluid comes into contact with the skin or eyes,
immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention
can be received.
● Always wash your hands after handling the battery support, terminals, and
other battery-related parts.
● Do not allow children near the 12-volt battery.
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entan-
gled in the cooling fan or belt.
■ Exclusive jump starting terminal
The exclusive jump starting terminal is to be used when charging the 12-volt
battery from another vehicle in an emergency. It cannot be used to jump start
another vehicle.
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5
When trouble arises
487
5-2. Steps to take in an emergency
If your vehicle overheats
Correction procedures■ If is shown on the mu lti-information display
Stop the vehicle in a safe place and turn off the air condition-
ing system, and then stop the hybrid system.
If you see steam: Carefully lift the hood after the steam subsides.
If you do not see steam: Carefully lift the hood.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core
(radiator) for any leaks.
Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
The following may indicate that your vehicle is overheating.
● ( P. 448) is shown on the multi-information display.
● The hybrid system overheat warning message ( P. 452) is
shown on the multi-information display.
● Steam comes out from under the hood.
STEP1
STEP2
STEP3
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488 5-2. Steps to take in an emergency
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL”
“LOW”
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
Start the hybrid system and turn the air conditioning system
on to check that the radiator cooling fan operates and to
check for coolant leaks from the radiator or hoses.
The fan operates when the air conditioning system is turned on
immediately after a cold start. Confirm that the fan is operating by
checking the fan sound and air flow. If it is difficult to check these,
turn the air conditioning system on and off repeatedly.
(The fan may not operate in freezing temperatures.)
If the fan is not operating: Stop the hybrid system im mediately and contact your
Toyota dealer.
If the fan is operating: Have the vehicle inspected at the nearest Toyota dealer.
STEP4
STEP5
STEP6
STEP7
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5
When trouble arises
489
5-2. Steps to take in an emergency
■
If the hybrid system overheat warning message is shown on
the multi-information display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has
cooled down, inspect the hoses
and radiator core (radiator) for
any leaks.
Radiator
Cooling fan
If a large amount of coolant leaks,
immediately contact your Toyota
dealer.
The coolant level is satisfactory if
it is between the “F” and “L” lines
on the reservoir.Reservoir
“F”
“L”
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
STEP1
STEP2
STEP3
STEP4
STEP5
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490 5-2. Steps to take in an emergency
Start the hybrid system and check for the multi-information
display.
If the message does not disappear:Stop the hybrid system and c ontact your Toyota dealer.
If the message is not displayed: Have the vehicle inspected at the nearest Toyota dealer.
CAUTION
■To prevent an accident or injury when inspecting under the hood of
your vehicle
● If steam is seen coming from under the hood, do not open the hood until
the steam has subsided. The engine compartment may be very hot, caus-
ing serious injuries such as burns.
● After the hybrid system has been turned off, check that on the
multi-information display and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automati-
cally start, or the cooling fan may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as the fan,
which may lead to fingers or clothing (especially a tie, a scarf or a muffler)
getting caught, resulting in serious injury.
● Do not loosen the radiator cap while the hybrid system and radiator are
hot.
Serious injuries, such as burns, may result from hot coolant and steam
released under pressure.
STEP6
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5
When trouble arises
491
5-2. Steps to take in an emergency
NOTICE
■
When adding engine/power control unit coolant
Wait until the hybrid system has cooled down before adding engine/power
control unit coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid sys-
tem too quickly can cause damage to the hybrid system.
■ To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust
etc.).
● Do not use any coolant additive.