2017 TOYOTA HIGHLANDER HYBRID cooling

5147-3. Do-it-yourself maintenance
HIGHLANDER_HV_U (OM48F12U)
Check the radiator and condenser and clear away any foreign objects.
If any of the above parts is extremel y dirty or you are not sure of their
condition, have your vehicle in spected by your Toyota dealer.
WARNING
■When the hybrid system is hot
Do not remove the engine/power control unit 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 hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause seri\
-
ous injuries, such as burns.

6308-2. Steps to take in an emergency
HIGHLANDER_HV_U (OM48F12U)
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entan-
gled in the cooling fans or belt.
■ Exclusive jump starting terminal
The exclusive jump starting terminal is intended to charge the 12-volt bat-
tery on your vehicle from another vehicle in an emergency. Do not use the
exclusive jump starting terminal to jump start another vehicle.

6318-2. Steps to take in an emergency
8
When trouble arises
HIGHLANDER_HV_U (OM48F12U)
●The needle of the engine coolant temperature gauge ( →P. 103)
enters the red zone or a loss of hybrid system power is experi-
enced. (For example, the vehicle speed does not increase.)
● “Hybrid System Overheated Reduced Output Power” is shown on
the multi-information display.
● Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters
the red zone
Stop the vehicle in a safe place and turn off the air conditioning
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 radia-
tor core (radiator) for any
leaks.Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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6328-2. Steps to take in an emergency
HIGHLANDER_HV_U (OM48F12U)
The coolant level is satisfac-
tory if it is between the
“FULL” and “LOW” lines on
the reservoir.Reservoir
“FULL”
“LOW”
Radiator cap
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 fans operate and to check for
coolant leaks from th e radiator or hoses.
The fans operate when the air conditioning system is turned on immedi-
ately after a cold start. Confirm that the fans are operating by checking
the fan sound and air flow. If it is difficult to check these, turn the air con-
ditioning system on and off repeatedly.
(The fan may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact your Toyota
dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Toyota dealer.
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6338-2. Steps to take in an emergency
8
When trouble arises
HIGHLANDER_HV_U (OM48F12U)■
If “Hybrid System Overheated Reduced Output Power” 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 fans
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
The coolant level is satisfac-
tory 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 check the multi-information display.
If the message does not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Toyota dealer.
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6348-2. Steps to take in an emergency
HIGHLANDER_HV_U (OM48F12U)
■Messages displays
The message illustrations used are intended as examples, and may differ
from the image that is actually displayed on the multi-information display.
WARNING
■When inspecting under the hood of your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
● 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.
● After the hybrid system has been turned off, check that the “READY” indi-
cator 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 and the coolant reservoir caps while the
hybrid system and radiator are hot.
High temperature steam or coolant could spray out.
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently.
Adding cool coolant to a hot hybrid system 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.

6449-1. Specifications
HIGHLANDER_HV_U (OM48F12U)
Cooling system
Capacity (reference)
Gasoline engine
Power control unit14.3 qt. (13.5 L, 11.9 Imp. qt.)
2.0 qt. (1.9 L, 1.7 Imp. qt.)
Coolant typeUse either of the following.
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based
non-silicate, non-amine, non-nitrite, and
non-borate coolant with long-life hybrid
organic acid technology
Do not use plain water alone.
Ignition system
Spark plug
MakeDENSO FK20HBR8
Gap0.031 in. (0.8 mm)
NOTICE
■ Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system
12-volt battery
Open voltage at 68 °F
(20° C): 12.0 V or More
If the voltage is lower than the standard value,
charge the battery.
(Voltage is checked 20 minutes after the hybrid
system and all lights are turned off.)
Charging rates5 A max.

701Alphabetical index
HIGHLANDER_HV_U (OM48F12U)
Care................................... 490, 494Aluminum wheels.................. 491
Exterior ................................. 490
Interior................................... 494
Seat belts .............................. 495
Cargo hooks............................. 457
CD player
*................................ 367
Chains....................................... 339
Child restraint system ............... 62
Booster seats, definition ......... 63
Booster seats, installation ....... 74
Convertible seats, definition ............................... 63
Convertible seats,
installation ............................ 70
Front passenger occupant classification syst em............. 54
Infant seats, definition ............. 63
Infant seats, installation .......... 70
Installing CRS with LATCH anchors .................... 68
Installing CRS with seat belts ...................................... 70
Installing CRS with top tether strap ........................... 76
Child safety ................................ 61 12-volt battery
precautions ................. 520, 629
Airbag precautions .................. 44
Back door precautions .......... 136
Child restraint system ............. 62
Glass hatch precautions ....... 143
How your child should wear the seat belt .......................... 37
Installing child restraints ......... 66
Moon roof precautions .......... 184 Panoramic moon roof
precautions......................... 189
Power window lock switch .... 178
Power window precautions ... 180
Rear door child-protectors .... 127
Removed electronic key battery precautions............. 540
Seat belt extender
precautions........................... 40
Seat belt precautions .............. 39
Seat heater precautions ....... 444
Child-protectors ...................... 127
Cleaning ........................... 490, 494 Aluminum wheels ................. 491
Exterior ................................. 490
Interior .................................. 494
Seat belts.............................. 495
Clock......................................... 461
Coat hooks ............................... 469
Compass .................................. 484
Condenser................................ 514
Console box ............................. 451
Conversation mirror ................ 460
Cooling system........................ 513 Hybrid system overheating ... 631
Cruise control Dynamic radar cruise
control ................................ 292
Cup holders ............................. 453
Curtain shield airbags............... 42
Customizable features ............ 666
C
*: Refer to “NAVIGATION AND MULTIMEDIA SYSTEM OWNER’S MANUAL”