2020 TOYOTA PRIUS PRIME coolant temperature

6648-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47C77U_(U)
High coolant temperature warning light• When the light flashes:Indicates that the engine coolant temperature is too high
The light changes from a flashing to a solid light when
the temperature further increases
 Immediately stop the vehicle in a safe place. ( P. 709)
• When the light comes on without flashing: Indicates a malfunction in the exhaust heat recirculator
system
 Have the vehicle inspected by your Toyota dealer
immediately.
(Flashes)
(If equipped)
PKSB OFF indicator
Indicates a malfunction in the Parking Support Brake func-
tion
 Have the vehicle inspected by your Toyota dealer.
The warning light will operate as follows, even when the
system is not malfunctioning:
• The light will come on when the Parking Support Brake function is turned off ( P. 444)
• The light will come on when the Parking Support Brake
function is operating ( P. 448)
• The light will flash when the system cannot be temporar- ily used ( P. 452)
Open door warning light (warning buzzer)*3
Indicates that a door is not fully closed
 Check that all the doors are closed.
Low fuel level warning light
Indicates that remaining fuel is approximately 1.7 gal.
(6.4 L, 1.4 Imp.gal.) or less
 Refuel the vehicle.
Driver’s and front passenger’ s seat belt reminder light
(warning buzzer)
*4, 5
Warns the driver and/or front passenger to fasten their
seat belts
 Fasten the seat belt.
If the front passenger’s seat is occupied, the front
passenger’s seat belt also needs to be fastened to
make the warning light (warning buzzer) turn off.
Warning lightWarning light/Details/Actions

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PRIUS PRIME_OM_OM47C77U_(U)
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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2
3
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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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2
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7128-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47C77U_(U)
After stopping the hybrid system and waiting for 5 minutes or
more, start the hybrid system again and check if “Hybrid System
Overheated” is shown on the multi-information display.
If the message d oes not disappear:
Stop the hybrid system and contact your Toyota dealer.
If the message is not displayed:
The hybrid system temperature has dropped and the vehicle may
be driven normally.
However, if the message appears again frequently, contact your Toyota
dealer.
WARNING
■ To prevent an accident or injury when inspecting under the hood of
your vehicle
Observe the following precautions.
Failure to do so may result in serious injury such as burns.
● If steam is seen coming from under the hood, do not open the ho od until
the steam has subsided. The engine compartment may be very hot.
● After the hybrid system has been turned off, check that the “Ac cessory”,
“Ignition ON” or mileage display ( P. 210) on the main display and the
“READY” indicator are off.
When the hybrid system is operating, the gasoline engine may au tomati-
cally start, or the cooling fans may suddenly operate even if the gasoline
engine stops. Do not touch or approach rotating parts such as the fan,
which may lead to fingers or clothing (especially a tie, a scarf or a muffler)
getting caught, resulting in serious injury.
● Do not loosen the coolant reservoir caps while the hybrid syste m and radi-
ator are hot.
High temperature steam or coolant could spray out.
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780Alphabetical index
PRIUS PRIME_OM_OM47C77U_(U)
Front seats ............................... 299Adjustment ............................ 299
Cleaning................................ 569
Correct driving posture ........... 28
Head restraints ..................... 303
Seat heaters ......................... 526
Front side marker lights.......... 350 Light switch ........................... 350
Replacing light bulbs............. 648
Front turn signal lights ........... 348 Replacing light bulbs............. 648
Turn signal lever ................... 348
Fuel ........................................... 368 Capacity ................................ 720
Fuel gauge ............................ 209
Information ............................ 727
Refueling............................... 368
Type ...................................... 720
Warning light ......................... 664
Fuel consumption.... 231, 263, 269
Average fuel consumption .... 231
Current fuel consumption...... 269
Fuel filler door.......................... 368
Opener .................................. 370
Refueling............................... 368
When the fuel filler door cannot be opened............... 371
Fuses ........................................ 638
Garage door opener ................ 555
Glove box ................................. 532 Hands-free system (for
cellular phone)
*
Head restraints ........................ 303
Head-up display....................... 251
Headlights ................................ 350
Automatic High Beam ........... 355
Headlight aim................ 641, 766
Light switch ........................... 350
Replacing light bulbs ............ 648
Heated steering wheel ............ 526
Heaters Automatic air conditioning system.... 500, 511
Heated steering wheel .......... 526
Hybrid battery (traction
battery) ............................... 135
Outside rear view
mirrors ........................ 504, 515
Seat heaters ......................... 526
High coolant temperature
warning light.......................... 664
High mounted stoplight Replacing.............................. 648
High-voltage components ........ 98
Hill-start assist control ........... 490
Hood ......................................... 585
Hooks Coat hooks ........................... 553
Grocery bag hook ................. 537
Retaining hooks (floor mat) .... 26
Horn .......................................... 306
HV mode ..................................... 87
G
H

789Alphabetical index
PRIUS PRIME_OM_OM47C77U_(U)
Vanity lights ............................. 540Wattage ................................ 726
Vanity mirrors .......................... 540
Vehicle data recording .............. 10
Vehicle identification number ................................... 719
Vehicle proximity notification system ...................................... 93
Vehicle Stability Control (VSC) ...................................... 489
Voice command system
*
VSC (Vehicle Stability
Control) .................................. 489
Warning buzzers Approach warning ................. 413
Brake system ....... ................. 662
Intuitive parking assist .......... 436
LDA (Lane Departure Alert with steering control) .......... 393
Open door ..................... 283, 664
Parking Support Brake function ............................... 448
Pre-collision warning............. 381
Radar cruise control.............. 413
RCTA (Rear Cross Traffic Alert) ................................... 421
Seat belt reminder ................ 664
Shift position ......................... 344 Warning lights ......................... 202
ABS ...................................... 663
Brake Override System ........ 666
Brake system ....... ................. 662
Charging system................... 662
Drive-Start Control ................ 666
Driver’s seat belt reminder light..................................... 664
Electronic engine control system .......... ...................... 662
Electric power steering
system .......... ...................... 663
Front passenger’s seat belt reminder light ..................... 664
High coolant temperature ..... 664
Low engine oil pressure........ 662
Low fuel level ........................ 664
Malfunction indicator lamp .... 662
Master warning light ............. 665
Open door............................. 664
Parking Support Brake function............................... 666
PCS ...................................... 663
PKSB OFF indicator ............. 664
Rear passengers’ seat belt
reminder light ..................... 665
Seat belt reminder light......... 664
Slip indicator ......................... 663
SRS ...................................... 663
Tire pressure ........................ 665
V
W
*: Refer to “NAVIGATION SYSTEM OWNER’S MANUAL” or “MULTIMEDIA OWNER’S MANUAL”.