2021 TOYOTA PRIUS PLUG-IN HYBRID heating

5846-1. Using the air conditioning system and defogger
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
NOTICE
■Humidity sensor
● Do not spray the glass cleaner on the sensor or subject it to strong impacts
● Do not stick anything on the sensor
■ To prevent 12-volt battery discharge
Do not leave the air conditioning syst em on longer than necessary when the
hybrid system is off.
■ Air outlets
The air outlets become hot when used for heating. Therefore, use caution
and adjust the air outlets accordingly.
In order to detect fog on the windshield, a
sensor which monitors the temperature
of the windshield, the surround humidity,
etc. is installed. ( P. 581)
Follow these points to avoid damaging
the sensor:
● Do not disassemble the sensor

5866-1. Using the air conditioning system and defogger
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Operating conditions
The system will only operate if all of the following conditions are met:
●The shift position is in P.
●The power switch is off.
*
●All doors are closed.
●The hood is closed.
*: The Remote Air Conditioning System cannot be used for approximately 3
minutes and a half after the power switch is turned off.
■Remote Air Conditioning System automatic shut-off
The system will automatically shut off under the following conditions:
●About 10 minutes have passed since operation began
●Any one of the operating conditions is not met
The system may also shut off if the charge level of the hybrid battery (traction
battery) drops to low.
■Conditions affecting operation
The system may not start in the following situations:
●The charge level of the hybrid battery (traction battery) is low
●The outside temperature is extremely low
●When the hybrid system is cool (for example, after being left for a long time
in low temperatures)
■Windshield defogger
When defogging the windshield using the Remote Air Conditioning System,
defogging may be insufficient due to the power being restricted more than
during normal air conditioning operation. Also, the outside of the windshield
may fog up due to the outside temperature, humidity or air conditioning set
temperature.
■Using the heater via the Remote Air Conditioning System
When the outside heat exchanger becomes frosted over, heating perfor-
mance may decline due to automatically switching to the frost removal opera-
tion.
■Security feature
Any unlocked doors will be automatically locked when the system is operat-
ing. The emergency flashers flash to indicate that the doors have been locked
or the system has been turned off.
(The doors locked: Once; The system turned off: Twice)
■Conditions affecting operation
P. 296

5896-1. Using the air conditioning system and defogger
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
6
Interior features
Seat heaters
Seat heaters heat the front seats.
WARNING
● Care should be taken to prevent injury if anyone in the following categories
comes in contact with the seats when the heater is on:
• Babies, small children, the elderly, the sick and the physically chal-
lenged
• Persons with sensitive skin
• Persons who are fatigued
• Persons who have taken alcohol or drugs that induce sleep (sleeping
drugs, cold remedies, etc.)
● Observe the following precautions to prevent minor burns or overheating:
• Do not cover the seat with a blanket or cushion when using the seat
heater.
• Do not use seat heater more than necessary.
NOTICE
● Do not put heavy objects that have an uneven surface on the seat and do
not stick sharp objects (needles, nails, etc.) into the seat.
● To prevent 12-volt battery discharge, do not use the functions when the
hybrid system is off.

7618-2. Steps to take in an emergency
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
8
When trouble arises
If your vehicle overheats
■If the high coolant temperature warning light comes on or
flashes
Stop 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 the
hoses and radiator core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant
leaks, immediately contact
any authorized Toyota retailer
or Toyota authorized repairer,
or any reliable repairer.
The following may indicate that your vehicle is overheating.
● The high coolant temperature warning light (P. 716) comes on
or flashes, or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
● “Hybrid System Overheated” is shown on the multi-information
display.
● Steam comes out from under the hood.
Correction procedures
1
2
3
1
2

801Alphabetical index
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
Child-protectors ....................... 286
Cleaning............................ 616, 622
Aluminum wheels .................. 617
Exterior.................................. 616
Front camera......................... 408
Hybrid battery (traction
battery) air intake vent ........ 623
Interior ................................... 622
Radar sensor ........................ 407
Seat belts .............................. 625
Water-repellent coating ......... 617
Clock ......................................... 204
Adjustment ............................ 210
Coat hooks ............................... 613
Combination meter .................. 204
Clock adjustment .................. 210
Main display .......................... 222
Multi-information display ....... 230
Warning lights and
indicators ............................ 214
Condenser ................................ 643
Console box ............................. 595
Consumption screen ............... 275
Coolant ..................................... 641
Capacity ................................ 776
Checking ............................... 641
Preparing and checking
before winter....................... 566
Cooling system ........................ 641
Engine overheating ............... 761
Hybrid system overheating ... 763
Cruise control
Dynamic radar cruise control
with full-speed range .......... 451
Cup holders .............................. 596
Curtain shield airbags ............... 39
Customizable features ............ 782Daytime running light
system .................................... 388
Deck board ............................... 600
Defogger
Outside rear view mirrors...... 577
Rear window ......................... 577
Windshield ............................ 577
Dimension ................................ 770
Display
Drive information................... 232
Dynamic radar cruise control
with full-speed range .......... 451
Energy monitor ............. 233, 272
Head-up display .................... 264
LTA (Lane Tracing Assist) .... 438
Main display .......................... 222
Multi-information display ....... 230
Parking Support Brake
function ............................... 516
Pre-collision warning............. 419
RCTA detection screen......... 473
RSA (Road Sign Assist)........ 446
S-IPA (Simple Intelligent
Parking Assist System) ...... 527
Toyota parking assist
sensor................................. 500
Warning messages ............... 723
Do-it-yourself maintenance .... 631
Door courtesy lights................ 591
Location ................................ 591
Wattage ................................ 779D

803Alphabetical index
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
Emergency brake signal ......... 560
Emergency flashers................. 704
Emergency brake signal ....... 560
Emergency tire puncture
repair kit ................................. 731
Energy monitor ................ 233, 272
Engine
Accessory mode ................... 375
Compartment ........................ 637
Engine switch ........................ 373
Exhaust gas precautions......... 50
Hood ..................................... 634
How to start the hybrid
system ................................ 373
Identification number............. 772
If the hybrid system will not
start..................................... 749
If your vehicle has to be
stopped in an emergency ... 705
Ignition switch (power
switch) ................................ 373
Overheating .......................... 761
Power switch ......................... 373
Engine coolant ......................... 641
Capacity ................................ 776
Checking ............................... 641
Preparing and checking
before winter....................... 566Engine oil ................................. 638
Capacity ................................ 773
Checking ............................... 638
Oil pressure warning light ..... 715
Preparing and checking
before winter....................... 566
Engine switch (power
switch) .................................... 373
Auto power off function ......... 375
Changing the power switch
modes................................. 375
If your vehicle has to be
stopped in an emergency ... 705
Starting the hybrid system .... 373
EPS (Electronic Power
Steering)................................. 560
Function ................................ 560
Warning light ......................... 715
EV City mode switch ................. 98
EV driving range ...................... 119
EV mode ..................................... 95
EV/HV mode selection
switch ....................................... 98
Exhaust gas precautions .......... 50

805Alphabetical index
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
Horn .......................................... 346
HV mode ..................................... 95
Hybrid battery (traction
battery) ................................... 108
Air intake vent ....................... 109
Charging ............................... 121
Location ................................ 108
Specification.......................... 773
Status indicator ..................... 123
Hybrid battery (traction
battery) air intake vent .......... 109
Cleaning ................................ 623
Hybrid system ............................ 94
Brake Override System ......... 360
Consumption screen ..... 244, 275
Drive-Start Control ................ 360
Emergency shut off system... 109
Energy monitor.............. 233, 272
High voltage components ..... 108
Hybrid System Indicator ........ 236
If the hybrid system will not
start..................................... 749
Overheating .......................... 761
Plug-in hybrid system
precautions ......................... 108
Plug-in hybrid vehicle driving
tips ...................................... 115
Power switch ......................... 373
Regenerative braking ............ 103
Starting the hybrid system .... 373
Vehicle proximity notification
system ................................ 103
Hybrid System Indicator ......... 236
Hybrid transmission ................ 379Identification ............................ 771
Engine................................... 772
Vehicle .................................. 771
Ignition switch (power
switch) .................................... 373
Auto power off function ......... 375
Changing the power switch
modes................................. 375
If your vehicle has to be
stopped in an emergency ... 705
Starting the hybrid system .... 373
Illuminated entry system ........ 593
Immobilizer system ................... 74
Indicators ................................. 214
Initialization .............................. 792
Items to initialize ................... 792
Parking Support Brake
function ............................... 520
Power windows ..................... 353
S-IPA (Simple Intelligent
Parking Assist System) ...... 548
Tire pressure warning
system ................................ 652
Inside rear view mirror ............ 348
Instrument cluster light
control .................................... 206
Interior lights............................ 591
Switch ........................... 592, 593
Wattage ................................ 779
Intrusion sensor ........................ 90
ISOFIX lower anchorages ......... 70I
*: Refer to “Navigation system Owner’s manual”.

808Alphabetical index
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
Navigation system*
Odometer .................................. 224
Oil
Engine oil .............................. 773
Opener
Back door .............................. 288
Fuel filler door ....................... 403
Hood ..................................... 634
Outside rear view mirrors ....... 350
Adjustment ............................ 350
BSM (Blind Spot Monitor) ..... 473
Folding .................................. 350
Outside rear view mirror
defoggers............................ 577
Outside temperature
display .................................... 222
Overhead console.................... 598
Overheating .............................. 761
P position switch ..................... 380
Panoramic view monitor
*
Parking assist sensors
Parking Support Brake
function ............................... 510
S-IPA (Simple Intelligent
Parking Assist System)....... 523
Toyota parking
assist-sensor ...................... 499Parking brake ........................... 386
Operation .............................. 386
Parking brake engaged
warning buzzer ................... 386
Parking lock ............................. 380
Parking Support Brake
function .................................. 510
PCS (Pre-Collision System) .... 418
Enabling/disabling the
system ................................ 422
Function ................................ 418
Warning light ......................... 716
Personal lights ......................... 591
Switch ................................... 592
Wattage ................................ 779
Plug-in hybrid system ............... 94
Driving tips ............................ 115
EV City mode .......................... 95
EV driving range ................... 119
EV mode ................................. 95
EV/HV mode selection
switch ................................... 98
Features.................................. 94
How to charge....................... 165
HV mode ................................. 95
Hybrid battery (traction
battery) charge mode ........... 95
Power control unit coolant ..... 641
Capacity ................................ 776
Checking ............................... 641
Preparing and checking
before winter....................... 566
Radiator ................................ 643
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