coolant temperature TOYOTA PRIUS PLUS 2012 Owners Manual

247 2-2. Instrument cluster
2
When driving
PRIUS +_OM_OM47821E_(EE)
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 cluster light
If the headlight switch is turned to ON while the surrounding area is dark, the
instrument cluster lights will dim.
When disconnecting and reconnecting 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. 528)
The trip information display 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.

392 4-2. Maintenance
PRIUS +_OM_OM47821E_(EE)
Flat-looking tires, excessive tire squeal when cornering, uneven tire wear
Vehicle pulls to one side when driving straight on a level road
Strange noises related to suspension movement
Loss of brake effectiveness, spongy feeling brake pedal, pedal almost
touches the floor, vehicle pulls to one side when braking
Engine coolant temperature continually higher than normal
If you notice any of these clues, take your vehicle to any authorized Toyota
dealer or repairer, or another duly qualified and equipped professional as
soon as possible. Your vehicle may need adjustment or repair.
CAUTION
If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and
possible serious injury or death.
Handling of the 12-volt battery
12-volt battery posts, terminals and related accessories contain lead and
lead compounds which are known to cause brain damage. Wash your hands
after handling. (P. 413)

409 4-3. Do-it-yourself maintenance
4
Maintenance and care
PRIUS +_OM_OM47821E_(EE)
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%
deionized water. (Minimum temperature: -35 C [-31 F])
For more details about coolant, contact any authorized Toyota dealer or
repairer, or another duly qualified and equipped professional.
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 any authorized Toyota dealer or repairer, or
another duly qualified and equipped professional 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.

468
5-1. Essential information
PRIUS +_OM_OM47821E_(EE)
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact any authorized Toyota dealer or
repairer, or another duly qualified and equipped professional as
soon as possible.
Visible symptoms
Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
Flat-looking tires or uneven tire wear
High engine coolant temperature warning light flashes or
comes on
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 roughly
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, spongy feeling, pedal almost
touches the floor

470 5-2. Steps to take in an emergency
PRIUS +_OM_OM47821E_(EE)
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 any authorized Toyota dealer or repairer, or
another duly qualified and equipped professional.
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 temperature 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

528
5-2. Steps to take in an emergency
PRIUS +_OM_OM47821E_(EE)
If your vehicle overheats
Correction procedures
If the high coolant temperature warning light comes on or
flashes
Stop the vehicle in a safe place and turn off the air condition-
ing 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.
The following may indicate that your vehicle is overheating.
The high coolant temperature warning light (P. 470) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
The hybrid system overheat warning light (P. 475) comes on.
Steam comes out from under the hood.
STEP 1
STEP 2

530 5-2. Steps to take in an emergency
PRIUS +_OM_OM47821E_(EE)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 the radiator or hoses.
The fans operate when the air conditioning system 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 air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact any autho-
rized Toyota dealer or repairer, or another duly qualified and
equipped professional.
If the fans are operating:
Have the vehicle inspected at the nearest any authorized
Toyota dealer or repairer, or another duly qualified and
equipped professional.
STEP 6
STEP7

572 Alphabetical index
PRIUS +_OM_OM47821E_(EE)
USB port*
Vanity lights
Vanity lights........................... 363
Wattage................................. 551
Vanity mirrors .......................... 363
Vehicle identification
number ................................... 541
Vehicle stability control .......... 298
VSC ........................................... 298
Warning buzzers
Brake system ........................ 469
Open door ............................ 476
Seat belt reminder................. 477Warning lights
Anti-lock brake system
(ABS) .................................. 471
Automatic headlight leveling
system ................................ 474
Brake system ................ 469, 472
Charging system ................... 470
Cruise control........................ 474
Electric power steering
system ................................ 471
High coolant temperature ..... 470
Hybrid battery indicator
light ..................................... 473
Hybrid system ....................... 470
Hybrid system overheat ........ 475
LED headlights ..................... 474
Low engine oil pressure ........ 470
Low fuel level ........................ 476
Low hybrid battery
(traction battery) ................. 476
Malfunction indicator lamp .... 471
Open door ............................. 476
Parking lock system .............. 473
P position request ................. 475
Pre-crash safety system ....... 472
Radar cruise control.............. 474
Seat belt warning light .......... 477
Slip indicator ......................... 472
Smart entry & start system ... 479
SRS airbags.......................... 471
U
V
W

574
PRIUS +_OM_OM47821E_(EE)
What to do if...
What to do if...
A tire puncturesP. 4 8 2 ,
494If you have a flat tire
The hybrid system does not start
P. 516If the hybrid system will not start
P. 143Immobilizer system
P. 522If 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. 528If your vehicle overheats
The key is lostP. 518If you lose your keys
The 12-volt battery runs outP. 522If the 12-volt battery is
discharged
The doors cannot be lockedP. 9 4Side doors
P. 9 7Back door
The vehicle is stuck in mud or
sandP. 534If the vehicle becomes stuck

575 What to do if...
PRIUS +_OM_OM47821E_(EE)
A warning light or indicator
light comes onP. 469If a warning light turns on or a
warning buzzer sounds
Warning lights
P. 469P. 471
P. 470P. 471
P. 470P. 471
P. 470P. 471
P. 470P. 472
Charging system
warning lightSRS warning light
Low engine oil pressure
warning lightABS warning light
High coolant
temperature warning
lightElectric power steering
system warning light
Hybrid system warning
lightPre-crash safety system
warning light*1
Brake system warning
light (red indicator)Malfunction indicator
lamp