2022 TOYOTA PRIUS PRIME heating

PRIUS PRIME_OM_OM47E74U_(U)
5256-1. Using the air conditioning system and defogger
6
Interior features
■Heating
●In HV mode, the gasoline engine may operate in order to extract heat from
the engine coolant via the heater.
● In EV mode, heating is done by a heat pump system.
• When the outside temperature is low or it is snowing, compared to con-
ventional vehicles, heating may be less effective and warm air may not
come out.
• If frost has formed of the outside heat exchanger, the heating perfor-
mance will decline. The frost can be removed from the outside heat
exchanger by operating the Remote Air Conditioning System befor e driv-
ing ( P. 531). When frosted over, the heating operation of the Remote
Air Conditioning System starts after defrosting.
• When is turned on, the heating is controlled optimally. There -
fore, the set heating performance may not be achieved even if the fan
speed setting is increased.
● In the following situations the gasoline engine may operate in order to
extract heat from the engine coolant via the heater even in EV mode.
• The outside temperature is approximately 14°F (-10°C) or low
• is operating
■ Using automatic mode
Fan speed is adjusted automatically according to the temperatur e setting and
the ambient conditions.
Therefore, the fan may stop for a while until warm or cool air is ready to flow
immediately after is pressed.
■ Water droplets during air conditioning operation• When the outside heat exchanger is
frosted over, fan speed declines and it
may become harder to heat the inte-
rior. However, it is not a malfunction.
In this situation, the air temperature
from the outlets may not change even
though the set temperature is raised.
The outside heat exchanger, accumulator
and air conditioning piping may incur con-
densation or frost may form. During or
after the air conditioning operation, water
droplets may fall from the vehicle. How-
ever, it is not a malfunction.
Outside heat exchanger
Outside heat exchanger
Accumulator

5306-1. Using the air conditioning system and defogger
PRIUS PRIME_OM_OM47E74U_(U)
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 system on longer than necessa ry when the
hybrid system is off.
■ When repairing/replacing parts of the air conditioning system
Have repair/replacement performed by your Toyota dealer. When a part of
the air conditioning system, such as the evaporator, is to be replaced, it
must be replaced with a new one.
■ Air outlets
The air outlets become hot when used for heating. Therefore, us e 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. 527)
Follow these points to avoid damaging
the sensor:
● Do not disassemble the sensor

5326-1. Using the air conditioning system and defogger
PRIUS PRIME_OM_OM47E74U_(U)
■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 approxim ately 3
minutes and a half after the power switch is turned off.
■ Remote Air Conditioning S ystem automatic shut-off
The system will automatically shut off under the following cond itions:
● 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 lo w
● The outside temperature is extremely low
● When the hybrid system is cool (for example, after being left f or 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 p erfor-
mance may decline due to automatically switching to the frost r emoval opera-
tion.

535
PRIUS PRIME_OM_OM47E74U_(U)
6-1. Using the air conditioning system and defogger
6
Interior features
Heated steering wheel/seat heaters
: If equipped
●Heated steering wheel
Warm up the grip of the steering wheel
● Seat heaters (front seats)
Warm up the seat upholstery
WARNING
●Care should be taken to prevent injury if anyone in the following categories
comes in contact with the steering wheel and seats when the hea ter 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 ove rheating:
• 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 sea t 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.

718
PRIUS PRIME_OM_OM47E74U_(U)
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. 673) 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
1
2
3
1
2

787Alphabetical index
PRIUS PRIME_OM_OM47E74U_(U)
Radar sensor ........................ 372
Seat belts .............................. 582
Water-repellent coating......... 575
Clock ......................................... 192 Adjustment ............................ 197
Coat hooks ............................... 562
Combination meter .................. 192 Clock adjustment .................. 197
Main display .......................... 209
Multi-information display ....... 220
Warning lights and
indicators ............................ 201
Condenser ................................ 604
Console box ............................. 541
Consumption screen ....... 264, 269
Coolant ..................................... 602 Capacity ................................ 731
Checking ............................... 602
Preparing and checking before winter....................... 502
Cooling system ........................ 602 Engine overheating ............... 718
Hybrid system overheating ... 720
Cruise control Dynamic radar cruise control with full-speed range .......... 409
Cup holders.............................. 542
Curtain shield airbags ............... 36
Customizable features ............ 749
Daytime running light system .................................... 350
Deck board ............................... 545
Defogger Outside rear view
mirrors ........................ 512, 523
Rear window ................. 512, 523
Windshield .................... 511, 523 Dimension ................................ 726
Dinghy towing.......................... 331
Display
BSM (Blind Spot Monitor) ..... 427
Drive information .................. 222
Dynamic radar cruise control with full-speed range .......... 409
Energy monitor ..... 223, 261, 266
Head-up display.................... 253
Intuitive parking assist .......... 442
LTA (Lane Tracing Assist) .... 399
Main display.......................... 209
Multi-information display ....... 220
Parking Support Brake
function............................... 457
Pre-collision warning ............ 380
RSA (Road Sign Assist) ....... 406
S-APGS (Simple Advanced Parking Guidance
System) .............................. 466
Warning messages ............... 681
Do-it-yourself maintenance .... 592
Door courtesy lights ............... 537 Location ................................ 537
Wattage ................................ 734
Doors ................................ 279, 285 Automatic door locking
and unlocking system......... 282
Back door ............................. 285
Door glasses......................... 309
Door lock .............................. 279
Open door warning buzzer ... 283
Open door warning light ....... 673
Outside rear view mirrors ..... 307
Rear door child-protectors .... 282
Side doors ............................ 279
Side windows........................ 309
D
*: Refer to “MULTIMEDIA OWNER’S MANUAL”.

789Alphabetical index
PRIUS PRIME_OM_OM47E74U_(U)
EngineAccessory mode ................... 334
Compartment ........................ 598
Engine switch........................ 332
Exhaust gas precautions ........ 56
Hood ..................................... 595
How to start the hybrid system ......... ....................... 332
Identification number ............ 728
If the hybrid system will not start .................................... 706
If your vehicle has to be stopped in an emergency ... 661
Ignition switch (power
switch) ................................ 332
Overheating .......................... 718
Power switch......................... 332
Engine coolant ......................... 602 Capacity ................................ 731
Checking ............................... 602
Preparing and checking before winter....................... 502
Engine oil ................................. 599
Capacity ................................ 730
Checking ............................... 599
Oil pressure warning light ..... 671
Preparing and checking before winter....................... 502
Engine switch (power switch) .................................... 332
Auto power off function ......... 334
Changing the power switch modes................................. 334
If your vehicle has to be stopped in an emergency ... 661
Starting the hybrid system .... 332 EPS (Electric Power
Steering) ................................ 497
Function ................................ 497
Warning light......................... 672
EV auto mode ............................ 87
EV driving range ...................... 109
EV mode ..................................... 87
EV/HV mode selection
switch ....................................... 90
Event data recorder (EDR)........ 11
Exhaust gas precautions .......... 56
Flat tire ..................................... 689
Floor mats .................................. 26
Fluid Brake .................................... 733
Transmission ........................ 732
Washer ................................. 610
Fog lights ................................. 357
Replacing light bulbs ............ 657
Switch ................................... 357
Footwell lights ......................... 537
Front doors .............................. 279
Front fog lights ........................ 357
Replacing light bulbs ............ 657
Switch ................................... 357
Front passenger occupant classification system .............. 50
Front passenger’s seat
belt reminder light................. 674
Front seat concentrated airflow mode
(S-FLOW) ....................... 510, 522
F

791Alphabetical index
PRIUS PRIME_OM_OM47E74U_(U)
Hybrid battery (traction battery) ..................................... 99
Air intake vent ....................... 100
Charging ............................... 111
Location .................................. 99
Specification ......................... 729
Status indicator ..................... 113
Hybrid battery (traction
battery) air intake vent .......... 100 Cleaning................................ 580
Hybrid system ............................ 86
Brake Override System......... 316
Consumption screen................. 233, 264, 269
Drive-Start Control ................ 316
Emergency shut off system .. 100
Energy monitor ..... 223, 261, 266
High voltage components ....... 99
Hybrid System Indicator........ 225
If the hybrid system will not start .................................... 706
Overheating .......................... 718
Plug-in hybrid system precautions ........................... 99
Plug-in hybrid vehicle driving tips ...................................... 106
Power switch......................... 332
Regenerative braking.............. 95
Starting the hybrid system .... 332
Vehicle proximity notification
system ......... ......................... 93
Hybrid System Indicator ......... 225
Hybrid transmission ................ 339 I/M test ...................................... 591
Identification ............................ 727
Engine .................................. 728
Vehicle .................................. 727
Ignition switch (power
switch).................................... 332 Auto power off function ......... 334
Changing the power switch modes ................................ 334
If your vehicle has to be stopped in an emergency ... 661
Starting the hybrid system .... 332
Illuminated entry system ........ 539
Immobilizer system ................... 83
Indicators ................................. 201
Initialization.............................. 761 Items to initialize ................... 761
Maintenance data ................. 586
Parking Support Brake function............................... 458
Power windows..................... 310
S-APGS (Simple Advanced Parking Guidance
System) .............................. 486
Tire pressure warning system .......... ...................... 614
Inside rear view mirror ............ 305
Instrument cluster light
control .................................... 194
Interior lights ........................... 537
Switch ........................... 538, 539
Wattage ................................ 734
Intuitive parking assist ........... 441I
*: Refer to “NAVIGATION SYSTEM OWNER’S MANUAL” or “MULTIMEDIA OWNER’S MANUAL”.