Page 506 of 676
506 4-3. Do-it-yourself maintenance
Power control unit coolant reservoirReservoir cap
“FULL”
“LOW”
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line.
■If the coolant level drops within a short time after replenishing
Visually check the radiator, hoses, coolant reservoir cap, drain cock and
water pump.
If you cannot find a leak, have your Toyota dealer test the cap opening pres-
sure and check for leaks in the cooling system.
■ Coolant selection
Only use “Toyota Super Long Life Coolant” or 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. (Enabled: -31 F [-35 C])
Canada: Toyota Super Long Life Coolant is a mixture of 55% coolant and 45% deionized water. (Enabled: -44 F [-42 C])
For more details about coolant, contact your Toyota dealer.
Page 507 of 676
507
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■
When the hybrid system is hot
Do not remove the coolant 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 damage to parts or paint.
Page 508 of 676

508 4-3. Do-it-yourself maintenance
Radiator and condenserCheck the radiators and condens er, and clear away any foreign
objects.
If either of the above parts are ex tremely dirty or you are not sure of
their condition, have your vehicl e checked by your Toyota dealer.
CAUTION
■When the hybrid system is hot
Do not touch the radiators or condenser as they may be hot and cause seri-
ous injuries, such as burns.
■ When the electric cooling fan is operating
Do not touch the engine compartment.
Vehicles without smart key system: The electric cooling fans may keep rotat-
ing for about 3 minutes after the engine switch is turned to the “LOCK” posi-
tion.
With the engine switch in the “ON” position, the electric cooling fans may
automatically start to run if the air conditioning is on and/or the coolant tem-
perature is high. Be sure the engine switch is in the “LOCK” position when
working near the electric cooling fan or radiator grille.
Vehicles with smart key system: The electric cooling fan may keep rotating
for about 3 minutes after the “POWER” switch is OFF.
With the “POWER” switch in ON mode, the electric cooling fan may automat-
ically start to run if the air conditioning is on and/or the coolant temperature
is high. Be sure the “POWER” switch is OFF when working near the electric
cooling fan or radiator grille.
Page 566 of 676
566
5-1. Essential information
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Toyota dealer as soon as
possible.
■ Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air cond itioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature g auge needle continually points
higher than normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
■ Operational symptoms
●Engine missing, stumbling or running rough
● 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, s pongy feeling, pedal almost
touches the floor
Page 602 of 676

602
5-2. Steps to take in an emergency
If your vehicle overheats
Correction procedures■ 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 condition-
ing system.
Check to see if steam is coming out from the engine area.
If you see steam:
Stop the hybrid system. Carefully lift the hood after the
steam subsides and then restart the hybrid system.
If you do not see steam: Leave the hybrid system operating and carefully lift the
hood.
Check if the cooling fans are operating.
If the fans are operating: Wait until the engine coolant temperature gauge begins to
fall and then stop the hybrid system.
If the fans are not operating: Stop the hybrid system immediately and call your Toyota
dealer.
The following may indicate that your vehicle is overheating:
●The needle of the engine coolant temperature gauge enters the
red zone:
The engine may be overheating.
● “Hybrid System Overheat” is shown on the multi-information dis-
play:
The power control unit may be overheating.
Follow the correction procedure as described below.
STEP1
STEP2
STEP3
Page 603 of 676
5
When trouble arises
603
5-2. Steps to take in an emergency
After the hybrid system has
cooled down, check the engine
coolant level and inspect the
cooling system for leaks.
If the engine compartment cover
needs to be removed. (
P. 501)
Engine coolant reservoir
Radiator
If necessary, add engine coolant
up to the “FULL” line.
Water can be used in an emer-
gency if engine coolant is unavail-
able. ( P. 617)
STEP4
STEP5
Page 604 of 676

604 5-2. Steps to take in an emergency
■If “Hybrid System Overheat” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place and turn off the air condition-
ing system.
Leave the hybrid system operating and carefully lift the hood.
Check if the cooling fans are operating.
If the fans are operating: Wait until “Hybrid System Overheat” disappears and then
stop the hybrid system.
If the message does not disapp ear, call your Toyota dealer.
If the fans are not operating: Stop the hybrid system immediately and call your Toyota
dealer.
After the hybrid system has
cooled down, check the power
control unit coolant level and
inspect the cooling system for
leaks.
If the engine compartment cover
needs to be removed. (P. 501)
Power control unit coolant res-
ervoir
Power control unit coolant
radiator
If necessary, add power control
unit coolant up to the “FULL”
line.
Water can be used in an emer-
gency if power control unit cool-
ant is unavailable. ( P. 617)
STEP1
STEP2
STEP3
STEP4
STEP5
Page 605 of 676

5
When trouble arises
605
5-2. Steps to take in an emergency
Have the vehicle inspected at your
nearest Toyota dealer as soon as
possible.
■ Overheating
The following symptoms may occur when your vehicle is overheating:
●Hybrid system output decreases.
● Steam comes from the engine area.
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 injury such as burns.
● With a hybrid vehicle, there are times when the gasoline engine automati-
cally starts to run or the cooling fans suddenly start to operate. Do not
touch or approach the rotating parts of the belt or fans. Doing so may lead
to fingers, clothes or tools getting caught, resulting in an accidental injury.
● Do not loosen the coolant reservoir cap while the hybrid system and radia-
tor are hot.
Serious injury, such as burns, may result from hot coolant and steam
released under pressure.
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.