Page 349 of 512
3496-3. Do-it-yourself maintenance
6
Maintenance and care
AVALON_HV_U (OM41451U)
■12-volt battery
P. 358
Engine compar tment
Fuse boxes ( P. 379)
Engine oil filler cap ( P. 351)
Engine oil level dipstick ( P. 350)
Brake fluid reservoir ( P. 356)
Engine coolant radiator ( P. 355) Power control unit coolant
radiator (
P. 355)
Condenser ( P. 355)
Electric cooling fans
Engine coolant reservoir ( P. 353)
Washer fluid tank ( P. 357)
Power control unit coolant res-
ervoir ( P. 353)1
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Page 353 of 512
3536-3. Do-it-yourself maintenance
6
Maintenance and care
AVALON_HV_U (OM41451U)
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
“F” line
“L” line
If the level is on or below the “L”
line, add coolant up to the “F”
line. ( P. 444)
■
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. ( P. 444)
Coolant
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Page 354 of 512

3546-3. Do-it-yourself maintenance
AVALON_HV_U (OM41451U)
■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.
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 F [-35 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.
CAUTION
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the
radiator cap.( P. 447)
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 straight 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 445 of 512
4457-2. Steps to take in an emergency
7
When trouble arises
AVALON_HV_U (OM41451U)
The coolant level is satisfac-
tory if it is between the “F”
and “L” lines on the reservoir.
Reservoir
“F” line
“L” line
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 th e radiator or hoses.
The fan operates when the air conditioning system is turned on immedi-
ately 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 condi-
tioning system on and off repeatedly.
(The fan may not operate in freezing temperatures.)
If the fan is not operating:
Stop the hybrid system immediately and contact your Toyota
dealer.
If the fan is operating:
Have the vehicle inspected at the nearest Toyota dealer.
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Page 446 of 512
4467-2. Steps to take in an emergency
AVALON_HV_U (OM41451U)■
If “Hybrid System Overheat/Stop the Vehicle in a Safe Place” 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 satisfac-
tory if it is between the
“FULL” and “LOW” lines on
the reservoir.
Reservoir
“FULL” line
“LOW” line
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
Start the hybrid system and chec k for the multi-information dis-
play.
If the message does not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is not displayed:
Have the vehicle in spected at the nearest Toyota dealer.
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Page 447 of 512

4477-2. Steps to take in an emergency
7
When trouble arises
AVALON_HV_U (OM41451U)
CAUTION
■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.
● Make sure that the “READY” indicator is off.
● Keep hands and clothing away from the fans, etc. while the hybrid system
is operating.
● On hybrid vehicles, the gasoline engine may automatically 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 fin-
gers or clothing (especially a tie, a scarf or a muffler) getting caught,
resulting in serious injury.
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 commercially available coolant additives.
●Do not loosen the radiator cap or the
coolant reservoir caps while the hybrid
system and radiator are hot.
High temperature steam or coolant
could spray out.