Page 420 of 596
4207-3. Do-it-yourself maintenance
PRIUS c_U
Engine compartment
Fuse boxes (P.   4 5 2 )
Engine oil filler cap ( P.   4 2 2 )
Engine coolant radiator cap
Power control unit 
coolant reservoir ( P.   4 2 4 )
Brake fluid reservoir ( P.   4 2 6 )
Engine coolant reservoir  ( P.   4 2 4 ) Engine/power  control  unit
coolant radiator (
P. 426)
Electric cooling fan
Condenser ( P. 426)
Engine oil level dipstick ( P. 421)
Washer fluid tank ( P. 428)1
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        Page 424 of 596
4247-3. Do-it-yourself maintenance
PRIUS c_U
Engine coolant reservoir
The coolant level is satisfact ory if it is between the “FULL” a nd “LOW”
lines on the reservoir wh en the engine is cold.
Reservoir cap
“FULL” line
“LOW” line
If  the  level  is  on  or  below  the
“LOW”  line,  add  coolant  up  to  the
“FULL” line. ( P. 526)
Power control unit coolant reservoir
The coolant level is satisfactory  if it is between the “F” and “L” lines on
the reservoir when the hybrid system is cold.
Reservoir cap
“F” line
“L” line
If  the  level  is  on  or  below  the  “L”
line,  add  coolant  up  to  the  “F”  line.
(P. 526)
Coolant
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        Page 425 of 596

4257-3. Do-it-yourself maintenance
7
Maintenance and care
PRIUS c_U
■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  an d  50%
deionized water. (Minimum temperature: -31 F [-35 C])
Canada: 
“Toyota  Super  Long  Life  Coolant”  is  a  mixture  of  55%  coolant  an d  45%
deionized 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  radiators,  hoses,  engine/power  control  unit  coolant  reser-
voir 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 systems.
WARNING
■ When the hybrid system is hot
Do not remove the engine coolant radiator cap and power control  unit cool-
ant 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 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. 
     
        
        Page 527 of 596
5278-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U
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 turn the air conditioning system on  to
check  that  the  radiator  cooling  fan  operates  and  to  check  for
coolant leaks from t he 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 neare st Toyota dealer.
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        Page 528 of 596
5288-2. Steps to take in an emergency
PRIUS c_U■
If  the  hybrid  system  overheat  warning  message  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 “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  chec k  for  the  multi-information  dis-
play.
If the message d oes not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is  not displayed:
Have the vehicle inspected at the neare st Toyota dealer.
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