2012 TOYOTA PRIUS V coolant temperature

207
2-2. Instrument cluster
PRIUS v_U (OM47784U)
2
When driving
■
Engine speed
On hybrid vehicles, engine speed is precisely controlled in order to help
improve fuel efficiency and reduce exhaust emissions etc.
There are times when the engine speed that is displayed may differ even
when vehicle operation and driving conditions are the same.
■ Brightness of the instrument panel light
If the headlight switch is turned to ON while the surrounding area is dark, the
instrument panel lights will dim.
■ When disconnecting and reconnect ing 12-volt battery terminals
The average fuel consumption and cruising range will be reset.
NOTICE
■ To prevent damage to the engine and its components
The engine may be overheating if the high coolant temperature warning light
comes on or flashes. In this case, immediately stop the vehicle in a safe
place, and check the engine after it has cooled completely. ( P. 487)
■ The trip information disp lay at low temperatures
Allow the interior of the vehicle to warm up before using the liquid crystal
information display. At extremely low temperatures, the information display
monitor may respond slowly, and display changes may be delayed.

378 4-3. Do-it-yourself maintenance
PRIUS v_U (OM47784U)
■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% cool- ant and 50% deionized water. (Minimum temperature: -31 F
[-35 C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% cool- ant and 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 radiator, 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 system.
CAUTION
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.

5
When trouble arises
445
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehi-
cle that may lead to an accident. Immediately stop the vehicle in a
safe place and contact your Toyota dealer.
Warning lightWarning light/Details
Charging system warning light Indicates a malfunction in the vehicle’s charging system
Low engine oil pressure warning light Indicates that the engine oil pressure is too low
High coolant temper ature warning light
Indicates that the coolant temperature is too high
Changes from a flashing to a solid light when the engine
coolant temperature increases.
Hybrid system warning light (warning buzzer) Indicates a malfunction in the hybrid system

5
When trouble arises
487
5-2. Steps to take in an emergency
PRIUS v_U (OM47784U)
If your vehicle overheats
Correction procedures■ If the high coolant temperature warning light flashes or comes
on
Stop the vehicle in a safe place and turn off the air condition-
ing system.
Check to see if steam is coming out from under the hood.
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 to see if the cooling fans are operating.
If the fans are operating: Wait until the high coolant temperature warning light goes
off 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 high coolant temperature warn ing light flashes or comes on:
The engine may be overheating.
● The hybrid system overhe at warning light comes on:
The power control unit may be overheating.
Follow the correction procedure as described below.
STEP 1
STEP 2
STEP 3

561
Alphabetical index
PRIUS v_U (OM47784U)
Warning buzzers
Brake system........................ 444
Open door ........................... 450
Seat belt reminder ................ 451
Warning lights Anti-lock brake system
(ABS) ................................. 446
Automatic headlight leveling system................................ 448
Brake system................ 444, 447
Charging system .... .............. 445
Cruise control ....................... 448
Electric power steering
system................................ 446
High coolant temperature ..... 445
Hybrid system....................... 445
Hybrid system overheat........ 449
LED headlights ..................... 448
Low engine oil pressure ....... 445
Low fuel level........................ 451
Low hybrid battery (traction battery) ................. 449
Low tire pressure .................. 451
Malfunction indicator lamp.... 446
Open door ............................ 450
Parking lock system ............. 447
P position request... .............. 449
Pre-collision system ............. 447
Radar cruise control. ............ 448
Seat belt warning light .......... 451
Slip indicator ......................... 447
Smart key system ... .............. 459
SRS airbags ......................... 446
Tire pressure warning light ... 451 Warning message
Parking lock system ..............448
Washer
Checking ...............................382
Preparing and checking before winter .......................273
Switch....................................223
Washing and waxing ...............348
Weight Cargo capacity ......................272
Load limits .............................272
Weight ...................................496
Wheels ......................................402
Window glasses .......................112
Window lock switch .................112
Windows Power windows .....................112
Rear window defogger ..........295
Washer ..................................223
Windshield wipers ...................223
Winter driving tips ...................273
Wireless remote control key Locking/Unlocking ...................72
Replacing the battery ............408
WMA disc
*
W
*: Refer to “Display Audio System Owner’s Manual” or “Navigation System Owner’s Manual”.

562
PRIUS v_U (OM47784U)
What to do if...
What to do if...
A tire puncturesP. 462If you have a flat tire
The hybrid system does not start
P. 476If the hybrid system will not start
P. 1 1 9Immobilizer system
P. 481If the 12-volt battery is
discharged
The high coolant temperature
warning light flashes or comes on
If the hybrid system overheat
warning light comes on
Steam can be seen coming
from under the hood
P. 487If your vehicle overheats
The key is lostP. 478If you lose your keys
The 12-volt battery runs outP. 481If the 12-volt battery is
discharged
The doors cannot be lockedP. 7 4Side doors
P. 7 9Back door
The vehicle is stuck in mud or
sandP. 491If the vehicle becomes stuck
A warning light or indicator
light comes onP. 444If a warning light turns on or a
warning buzzer sounds