2020 TOYOTA PRIUS PRIME radiator

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PRIUS PRIME_OM_OM47C77U_(U)
7-2. Maintenance
General maintenance
Listed below are the general maintenance items that should be
performed at the intervals specified in the “Owner’s Warranty
Information Booklet” or “Own er’s Manual Supplement/Sched-
uled Maintenance Guide”. It is recommended that any problem
you notice should be brought to the attention of your Toyota
dealer or qualified s ervice shop for advice.
Engine compartment
ItemsCheck points
12-volt batteryCheck the connections. (P. 595)
Brake fluidIs the brake fluid at the correct level? ( P. 598)
Engine/power control
unit coolantIs the engine/power control unit coolant at the
correct level? (P. 592)
Engine oilIs the engine oil at the correct level? (P. 589)
Exhaust systemThere should not be any fumes or strange
sounds.
Radiator/condenserThe radiator and condenser should be free from
foreign objects. (P. 594)
Washer fluidIs there sufficient washer fluid? (P. 600)

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7-3. Do-it-yourself maintenance
Do-it-yourself ser vice precautions
If you perform maintenance by yourself, be sure to follow the
correct procedure as given in these sections.
ItemsParts and tools
12-volt battery
condition
(  P. 5 9 5 )•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
( P. 5 9 8 )
• SAE J1703 or FMVSS No.116 DOT 3 or SAE J1704
or FMVSS No.116 DOT 4 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power
control unit cool-
ant level
( P. 5 9 2 )
• “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
For the U.S.A.:
“Toyota Super Long Life Coolant” is pre-mixed with
50% coolant and 50% deionized water.
For Canada:
“Toyota Super Long Life Coolant” is pre-mixed with
55% coolant and 45% deionized water.
• Funnel (used only for adding coolant)
Engine oil level
( P. 5 8 9 )• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses ( P. 638)• Fuse with same amperage rating as original
Hybrid battery
(traction battery)
air intake vent
( P. 5 7 0 )
• Vacuum cleaner, etc.• Flathead screwdriver
Headlight aim
( P. 6 4 1 )• Phillips-head screwdriver
Light bulbs
( P. 6 4 3 )• Bulb with same number and wattage rating as origi-
nal
• Flathead screwdriver• Wrench
Radiator and con-
denser ( P. 594)

PRIUS PRIME_OM_OM47C77U_(U)
5837-3. Do-it-yourself maintenance
7
Maintenance and care
Tire inflation
pressure
( P. 611)• Tire pressure gauge
• Compressed air source
Washer fluid
( P. 600)• Water or washer fluid containing antifreeze (for win-
ter use)
• Funnel (used only for adding water or washer fluid)
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”, “Ignition ON” or mileage display
(P. 210) on the main display and the “READY” indicator are both off.
● Keep hands, clothing and tools away from the moving fan.
● Be careful not to touch the engine, power control unit, radiato r, 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 r ags, in the
engine compartment.
● Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes
are flammable.
● Be extremely cautious when working on the 12-volt battery. It contains poi-
sonous and corrosive sulfuric acid.
■ When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature
is high. (P. 594)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.
from getting in your eyes.
ItemsParts and tools

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7-3. Do-it-yourself maintenance
Engine compartment
Engine coolant reservoir ( P. 592)
Fuse boxes ( P. 638)
Engine oil level dipstick ( P. 589)
Engine oil filler cap ( P. 590)
Brake fluid reservoir ( P. 598) Washer fluid tank (
P. 600)
12-volt battery ( P. 595)
Power control unit coolant
reservoir ( P. 592)
Radiator ( P. 594)
Condenser ( P. 594)
Electric cooling fans1
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PRIUS PRIME_OM_OM47C77U_(U)
5937-3. Do-it-yourself maintenance
7
Maintenance and care
■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-bora te 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 c oolant 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.
WARNING
■ When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir c aps.
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 cor rect 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 p arts or paint.

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7-3. Do-it-yourself maintenance
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of
their condition, have your vehicle inspected by your Toyota dea l e r.
Radiator and condenser
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and c ause seri-
ous injuries, such as burns.
■ When the electric cooling fans are operating
Do not touch the engine compartment.
With the power switch in ON mode, the electric cooling fans may automati-
cally 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 cool-
ing fans or radiator grille.

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8
When trouble arises
8-2. Steps to take in an emergency
If your vehicle overheats
■If the high coolant temperature warning light comes on or
flashesStop 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 t he
hoses and radiator core (ra diator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact
your Toyota dealer.
The following may indicate that your vehicle is overheating.
● The high coolant temperature warning light ( P. 664) comes on
or flashes, or a loss of hybrid system power is experienced. (F or
example, the vehicle s peed does not increase.)
● “Hybrid System Overheated” is shown on the multi-information
display.
● Steam comes out from under the hood.
Correction procedures
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7108-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47C77U_(U)
The coolant level is satisfactory 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 turn the air conditioning system on to
check that the radiator cooling fans operate and to check for
coolant leaks from t he radiator or hoses.
The fans operate when the temperature setting is adjusted to “LO” and
“A/C” switch (
*1 • *2) is turned on immediately 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 “A/C” switch
(
*1 • *2) on and off repeatedly. (The fans may not
operate in freezing temperatures.)
*1: Vehicles with 7-inch display
*2: Vehicles with 11.6-inch display
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 neare st Toyota dealer.
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