2017 TOYOTA HIGHLANDER HYBRID cooling

841-2. Hybrid system
HIGHLANDER_HV_U (OM48F12U)■
Sounds and vibrations specific to a hybrid vehicle
There may be no engine sound or vibration even though the vehicle is able to
move with the “READY” indicator is illuminated. Always shift the shift lever to
P when parked.
The following sounds or vibrations may occur when the hybrid system is
operating and are not a malfunction:
●Motor sounds may be heard from the engine compartment.
● Sounds may be heard from the hybrid battery (traction battery) under t\
he
rear seats when the hybrid system starts or stops.
● Relay operating sounds such as a snap or soft clank will be emitted from the
hybrid battery (traction battery), behind the rear seats, when the hybrid sys-
tem is started or stopped.
● Sounds from the hybrid system may be heard when the back door is open.
● Sounds may be heard from the transmission when the gasoline engine
starts or stops, when driving at low speeds, or during idling.
● Engine sounds may be heard when accelerating sharply.
● Sounds may be heard due to regenerative braking when the brake pedal is
depressed or as the accelerator pedal is released.
● Vibration may be felt when the gasoline engine starts or stops.
● Cooling fan sounds may be heard from the air intake vents under the rear\
seat.
■ Vehicle Proximity Notification System
In the following cases, the Vehicle Proximity Notification System sound may
be difficult for pedestrians, people ridi ng bicycles or other people and vehicles
in the surrounding area to hear:
● When there is a lot of noise in the vicinity
● When it is raining or during strong winds
● When in the area surrounding the rear of the vehicle, rather than in front of
the vehicle
■ Maintenance, repair, recycling, and disposal
Contact your Toyota dealer regarding maintenance, repair, recycling and dis-
posal. Do not dispose of the vehicle yourself.
■ Customization
Settings (e.g. on/off operation of the EV indicator) can be changed.
(Customizable features →P. 666)

861-2. Hybrid system
HIGHLANDER_HV_U (OM48F12U)
There are air intake vents under
the second seats for the purpose
of cooling the hybrid battery (trac-
tion battery). If the vents become
blocked, the hybrid battery may
overheat, leading to a reduction in
hybrid battery output.
When a certain level of impact is detected by the impact sensor, the
emergency shut off system blocks the high voltage current and stops
the fuel pump to minimize the risk of electrocution and fuel leakage. If
the emergency shut off sy stem activates, your vehicle will not restart.
To restart the hybrid system, contact your Toyota dealer.
A message is automatically displa yed when a malfunction occurs in
the hybrid system or an improper operation is attempted.
If a warning message is shown on
the multi-information display, read
the message and follow the
instructions. ( →P. 577)
Hybrid battery (traction battery) air intake vents
Emergency shut off system
Hybrid warning message

2364-2. Driving procedures
HIGHLANDER_HV_U (OM48F12U)
■Operation of the air conditio ning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the
air conditioning system to enhance fuel efficiency. ( →P. 434) To improve air
conditioning performance, adjust the fan speed or turn off Eco drive mode.
■ Automatic return to normal driving mode
If EV drive mode is selected, the driving mode will automatically return to nor-
mal mode when the hybrid system is turned off.
■ S mode
●When the shift range is 5 or lower, holding the shift lever toward “+” sets the
shift range to 6.
● To prevent the engine from over-revving, upshifting may automatically
occur.
■ When driving with dynamic radar cruise control activated
Even when performing the following actions with the intent of enabling engine
braking, engine braking will not activate while driving in S mode and down-
shifting to 5 or 4 because dynamic radar cruise control will not be canceled.
(→P. 292)
■ Shift lock system
The shift lock system is a system to prevent accidental operation of the shift
lever in starting.
The shift lever can be shifted from P only when the power switch is in ON
mode and the brake pedal is being depressed.

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HIGHLANDER_HV_U (OM48F12U)
4-6. Driving tips
◆Using Eco drive mode
When using Eco drive mode, the torque corresponding to the accel-
erator pedal depression amount can be generated more smoothly
than it is in normal conditions. In addition, the operation of the air
conditioning system (h eating/cooling) will be minimized, improving
the fuel economy. ( →P. 434)
◆Use of Hybrid System Indicator
The Eco-friendly driving is possible by keeping the indicate of
Hybrid System Indicator within Eco area. ( →P. 105)
◆Shift lever operation
Shift the shift lever to D when stopped at a traffic light, or driving in
heavy traffic, etc. Shift the shift lever to P when parking. When
using the N, there is no positive effect on fuel consumption. In the
N, the gasoline engine operates but electricity cannot be gener-
ated. Also, when using the air cond itioning system, etc., the hybrid
battery (traction batter y) power is consumed.
◆Accelerator pedal/brake pedal operation
●Drive your vehicle smoothly. Avoid abrupt acceleration and
deceleration. Gradual accelerati on and deceleration will make
more effective use of the electric motor (traction motor) without
having to use gasoline engine power.
● Avoid repeated acceleration. Repeated acceleration consumes
hybrid battery (traction battery) power, resulting in poor fuel con-
sumption. Battery power can be restored by driving with the
accelerator pedal slightly released.
Hybrid vehicle driving tips
For economical and ecological driv ing, pay attention to the fol-
lowing points:

4396-1. Using the air conditioning system and defogger
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Interior features
HIGHLANDER_HV_U (OM48F12U)■
Fogging up of the windows
●The windows will easily fog up when the humidity in the vehicle is high.
Turning on will dehumidify the air from the outlets and defog the wind-
shield effectively.
● If you turn off, the windows may fog up more easily.
● The windows may fog up if the recirculated air mode is used.
■ Windshield fog detection function
When automatic mode is set, the humidity sensor ( →P. 440) detects fog on
the windshield and controls the air conditioning system to prevent fog.
■ Outside/recirculated air mode
●When driving on dusty roads such as tunnels or in heavy traffic, set the out-
side/recirculated air mode button to the recirculated air mode. This is effec-
tive in preventing outside air from entering the vehicle interior. During
cooling operation, setting the recirculated air mode will also cool the vehicle
interior effectively.
● Outside/recirculated air mode may automatically switch depending on the
temperature setting or the inside temperature.
■ When the outside temperature exceeds 75°F (24°C) and the air condition-
ing system is on
● In order to reduce the air conditioning power consumption, the air condition-
ing system may switch to recirculated air mode automatically. This may also
reduce fuel consumption.
● Recirculated air mode is selected as a default mode when the power switch
is turned to ON mode.
● It is possible to switch to outside air mode at any time by pressing .
■ Ventilation and air conditioning odors
●To let fresh air in, set the air conditioning system to the outside air m\
ode.
● During use, various odors from inside and outside the vehicle may enter into
and accumulate in the air conditioning system. This may then cause odor to
be emitted from the vents.
● To reduce potential odors from occurring:
• It is recommended that the air conditioning system be set to outside air
mode prior to turning the vehicle off.
• The start timing of the blower may be delayed for a short period of time immediately after the air conditioning system is started in automatic
mode.
■ Air conditioning filter
→P. 537
■ Customization
Settings (e.g. A/C auto switch operation) can be changed.
(Customizable features →P. 666)

5057-3. Do-it-yourself maintenance
7
Maintenance and care
HIGHLANDER_HV_U (OM48F12U)
WARNING
The engine compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become electrically energized. To avoid death
or serious injury, observe the following precautions.
■When working on the engine compartment
● Make sure that the “ACCESSORY” or “IGNITION ON” on the multi-infor-
mation display and the “READY” indicator are both off.
● Keep hands, clothing and tools away from the moving fans and engine
drive belt.
● Be careful not to touch the engine, power control unit, radiator, exhaust
manifold, etc. right after driving as they may be hot. Oil and other fluids
may also be hot.
● Do not leave anything that may burn easily, such as paper and rags, in the
engine compartment.
● Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes
are flammable.
■ When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, t he electric cooling fans may automati-
cally start to run if the air condition ing is on and/or the coolant temperature
is high. ( →P. 514)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.
from getting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear
due to dirt in the air.

5097-3. Do-it-yourself maintenance
7
Maintenance and care
HIGHLANDER_HV_U (OM48F12U)
Engine compartment
Washer fluid tank (→P. 516)
Brake fluid reservoir (→ P. 515)
Engine oil filler cap (→ P. 5 11 )
Engine oil level dipstick (→ P. 510)
Engine coolant reservoir (→ P. 513) Power control unit coolant
reservoir (
→P. 513)
Fuse boxes ( →P. 541)
Electric cooling fans
Condenser ( →P. 514)
Power control unit coolant
radiator (→ P. 514)
Radiator ( →P. 514)1
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5137-3. Do-it-yourself maintenance
7
Maintenance and care
HIGHLANDER_HV_U (OM48F12U)
The coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the hybrid system is cold.
Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■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% deion-
ized water. (Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized 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 radiator, hoses, engine/power control unit coolant reservoir
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 system.
Coolant
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