2015 TOYOTA PRIUS PLUG-IN HYBRID coolant temperature

266 2-2. Instrument cluster
PRIUS PHV_OM_OM47A11U_(U)
CAUTION
■To prevent an accident
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. 607)
Do not place anything or attach a sticker
in front of the instrument cluster. The item
may obscure or obstruct the display, or
could reflect off the display, possibly
causing an accident.Instrument cluster

470 4-3. Do-it-yourself maintenance
PRIUS PHV_OM_OM47A11U_(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-borate coolant
with long-life hybrid organic acid technology.
U.S.A.: “Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deionized water. (M inimum temperature: -31F [-35 C])
Canada: “Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deionized water. (M inimum 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.

538 5-2. Steps to take in an emergency
PRIUS PHV_OM_OM47A11U_(U)
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
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.

5
When trouble arises
607
5-2. Steps to take in an emergency
PRIUS PHV_OM_OM47A11U_(U)
If your vehicle overheats
Correction procedures■ If the high coolant temperatur e 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.
After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core
(radiator) 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. 538) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle s peed does not increase.)
● “HYBRID SYSTEM OVERHEAT” ( P. 557) is shown on the
multi-informat ion display.
● Steam comes out from under the hood.
1 ÉTAPE
2 ÉTAPE
STEP 3

608 5-2. Steps to take in an emergency
PRIUS PHV_OM_OM47A11U_(U)
The coolant level is satisfactory if
it is between the “FULL” and
“LOW ” lines on the reservoir.Reservoir
“FULL”
“LOW ”
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 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 im mediately and contact your
Toyota dealer.
If the fans are operating: Have the vehicle inspected at the nearest Toyota dealer.
ITO43P111
STEP 4
ITO52P130
STEP 5
6 ÉTAPE
STEP7

610 5-2. Steps to take in an emergency
PRIUS PHV_OM_OM47A11U_(U)
Add coolant if necessary.
Water can be used in an emer-
gency if coolant is unavailable.
If water was added in an emer-
gency, have the vehicle inspected
at your Toyota dealer as soon as
possible.
After stopping the hybrid system and waiting for 5 minutes or
more, start the hybrid system again and check the multi-infor-
mation display.
If the message does not disappear:Stop the hybrid system and c ontact your Toyota dealer.
If the message is not displayed: The hybrid system temperature has dropped and the vehi-
cle may be driven normally.
However, if the message appears again frequently, contact your
Toyota dealer.
STEP 5
STEP 6

686 Alphabetical index
PRIUS PHV_OM_OM47A11U_(U)
Tonneau cover ......................... 410
Tools ......................................... 454
Total load capacity................... 354
Touch tracer display ................263
TowingDinghy towing........................ 361
Emergency towing................. 532
Trailer towing......................... 360
TRAC ......................................... 333
Traction control........................ 333
Trailer towing ........................... 360
Transmission
Hybrid transmission............... 249
P position switch ................... 252
Trip information ....................... 279
Trip meter ................................. 278
Turn signal lights Replacing light bulbs ............. 511
Switch.................................... 259
Wattage ................................. 628
USB port
*................................. 387
Vanity lights Vanity lights ........................... 399
Wattage ................................. 628
Vanity mirrors........................... 399
Vehicle data recordings ............24
Vehicle identification number ................................... 619
Vehicle proximity notification system ......................................38
Vehicle stability control........... 333
VSC............................................ 333 Warning buzzers
Brake system ........................ 537
Open door ............................ 541
Seat belt reminder................. 541
Warning lights Anti-lock brake system
(ABS) .................................. 539
Automatic headlight leveling system ................................ 540
Brake system ................ 537, 540
Charging system .... ............... 538
Cruise control ........................ 540
Electric power steering
system ................................ 539
High coolant temperature...... 538
Hybrid system ....................... 539
Low fuel level ........................ 541
Low tire pressure .................. 542
Malfunction indicator lamp .... 539
Open door ............................. 541
Pre-collision system .............. 540
Radar cruise control. ............. 540
Seat belt warning light........... 541
Slip indicator ......................... 540
SRS airbags .......................... 539
Tire pressure warning light.... 542U
V
W

688
PRIUS PHV_OM_OM47A11U_(U)
What to do if...
What to do if...
A tire puncturesP. 574If you have a flat tire
The hybrid system does not start
P. 596If the hybrid system will not start
P. 183Immobilizer system
P. 601If the 12-volt battery is
discharged
The high coolant temperature
warning light flashes or comes on
“HYBRID SYSTEM OVERHEAT”
is displayed
Steam can be seen coming
from under the hood
P. 607If your vehicle overheats
The key is lostP. 598If you lose your keys
The 12-volt battery runs outP. 601If the 12-volt battery is
discharged
The doors cannot be lockedP. 138Side doors
P. 144Back door
The vehicle is stuck in mud or
sandP. 613If the vehicle becomes stuck
A warning light or indicator
light comes onP. 537If a warning light turns on or a
warning buzzer sounds