engine overheat TOYOTA PRIUS PRIME 2022 Owners Manual

17Pictorial index
PRIUS PRIME_OM_OM47E74U_(U)Fuel filler door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 365
Refueling method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 365
Fuel type/fuel tank capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 728
Charging port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 111
Charging method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 135
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . P. 612
Replacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 626
Tire size/inflation pressure . . . . . . . . . . . . . . . . . . . . . . . . . P. 733
Winter tires/tire chain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 502
Checking/rotation/tire pressur e warning system . . . . . . . . .P. 612
Coping with flat tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 689
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 595
Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 595
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 730
Coping with overheat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 718
Headlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
Parking lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
Fog lights
* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 357
LED accent lights
*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
Turn signal lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 345
Daytime running lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
Side marker lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
Tail lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
License plate lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P. 347
Back-up lights
Shifting the shift position to R . . . . . . . . . . . . . . . . . . . . . . . . . P. 339
5
6
7
8
Light bulbs of the exterior lights for driving
(Replacing method: P. 652, Watts: P. 734)
*: If equipped
9
10
11
12
13
14
15
16
17
18

208
PRIUS PRIME_OM_OM47E74U_(U)
3. Instrument cluster
■BSM (Blind Spot Monitor) outsid e rear view mirror indicators
(if equipped) ( P. 427)
• When the BSM function is enabled on the screen of the multi-infor- mation display, the power switch is turned to ON mode.
If the system is functioning correctly, the BSM outside rear vi ew mirror indi-
cators will turn off after a few seconds.
If the BSM outside rear view mirror indicators do not illuminat e or do not
turn off, there may be a malfunction in the system.
If this occurs, have the vehicle inspected by your Toyota deale r.
●
Indicators are also displayed on the out-
side rear view mirrors.
● In order to confirm operation, the BSM
outside rear view mirror indicators illumi-
nate in the following situations:
• When the power switch is in ON
mode, the BSM function is enabled
on the screen of the multi-infor-
mation display.
WARNING
■If a safety system warning light does not come on
Should a safety system light such as the ABS and SRS warning li ght not
come on when you start the hybrid system, this could mean that these sys-
tems are not available to help protect you in an accident, which could result
in death or serious injury. Have the vehicle inspected by your Toyota dealer
immediately if this occurs.
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 v ehicle in a
safe place, and check the engine after it has cooled completely. (P. 718)

PRIUS PRIME_OM_OM47E74U_(U)
3195-1. Before driving
5
Driving
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When driving the vehicle
● Use engine braking (shift position B instead of shift position D) to maintain
a safe speed when driving down a steep hill.
Using the brakes continuously may cause the brakes to overheat and lose
effectiveness. ( P. 340)
● Do not adjust the positions of the steering wheel, the seat, or the inside or
outside rear view mirrors while driving.
Doing so may result in a loss of vehicle control.
● Always check that all passengers’ arms, head or other parts of their body
are not outside the vehicle.
● Do not drive across river crossings or through other bodies of water.
This may cause electric/electronic components to short circuit, damage
the hybrid system or cause other serious damage to the vehicle.
● Do not drive in excess of the speed limit. Even if the legal sp eed limit per-
mits it, do not drive over 85 mph (140 km/h) unless your vehicl e has high-
speed capability tires. Driving over 85 mph (140 km/h) may resu lt in tire
failure, loss of control and possible injury. Be sure to consult a tire dealer
to determine whether the tires on your vehicle are high-speed capability
tires or not before driving at such speeds.
■ When driving on slippery road surfaces
● Sudden braking, acceleration and steering may cause tire slippa ge and
reduce your ability to control the vehicle.
● Sudden acceleration, engine braking due to shifting, or changes in engine
speed could cause the vehicle to skid, resulting in an accident.
● After driving through a puddle, depress the brake pedal to make sure that
the brakes are functioning properly. Wet brake pads may prevent the
brakes from functioning properly. If the brakes on only one sid e are wet
and not functioning properly, steering control may be affected.

PRIUS PRIME_OM_OM47E74U_(U)
3215-1. Before driving
5
Driving
WARNING
Observe the following precautions.
Failure to do so may result in death or serious injury.
■If you hear a squealing or scraping noise (brake pad wear limit indica-
tors)
Have the brake pads checked and replaced by your Toyota dealer as soon
as possible.
Rotor damage may result if the pads are not replaced when neede d.
It is dangerous to drive the vehicle when the wear limits of the brake pads
and/or those of the brake discs are exceeded.
■ When the vehicle is stopped
● Do not depress the accelerator pedal unnecessarily.
If the shift position is in any position other than P or N, the vehicle may
accelerate suddenly and unexpectedly, causing an accident.
● In order to prevent accidents due to the vehicle rolling away, always keep
depressing the brake pedal while stopped with the “READY” indicator is
illuminated, and apply the parking brake as necessary.
● If the vehicle is stopped on an incline, in order to prevent ac cidents caused
by the vehicle rolling forward or backward, always depress the brake pedal
and securely apply the parking brake as needed.
● Avoid revving or racing the engine.
Running the engine at high speed while the vehicle is stopped may cause
the exhaust system to overheat, which could result in a fire if combustible
material is nearby.

PRIUS PRIME_OM_OM47E74U_(U)
4995-5. Using the driving support systems
5
Driving
■ECB operating sound
ECB operating sound may be heard in the following cases, but it does not
indicate that a malfunction has occurred.
● Operating sound heard from the engine compartment when the brak e pedal
is operated.
● Motor sound of the brake system heard from the front part of th e vehicle
when the driver’s door is opened.
● Operating sound heard from the engine compartment when one or t wo min-
utes passed after the stop of the hybrid system.
■ EPS operation sound
When the steering wheel is operated, a motor sound (whirring so und) may be
heard. This does not indicate a malfunction.
■ Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
● When the power switch is turned off
● If only the TRAC system is turned off, the TRAC will turn on wh en vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-e nabling
will not occur when vehicle speed increases.
■ Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the s ystem from
overheating when there is frequent steering input over an exten ded period of
time. The steering wheel may feel heavy as a result. Should thi s occur, refrain
from excessive steering input or stop the vehicle and turn the hybrid system
off. The EPS system should return to normal within 10 minutes.
■ Electric power steering system wa rning light (warning buzzer)
P. 672

6868-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47E74U_(U)■
If “Shifted into Shift Again to Start Vehicle” is shown
Message is displayed when the automatic P position selection function oper-
ates. ( P. 342)
To start off the vehicle after the shift position is changed to P, operate the shift
lever again.
■ If “Shift to Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without t urning the
power switch to off with the shift position in any position oth er than P.
Shift the shift position to P.
■ If “Shift is in Release Accelerat or Before Shifting” is shown
Message is displayed when the accelerator pedal has been depressed and
the shift position is in N.
Release the accelerator pedal and shift the shift position to D or R.
■ If “Depress Brake When Vehicle is Stopped. Hybrid System may Ov er-
heat.” is shown
The message may be shown when the accelerator pedal is depresse d to hold
the vehicle while the vehicle is stopped on an uphill, etc.
The hybrid system may overheat. Release the accelerator pedal a nd depress
the brake pedal.
■ If “Shifted to Stop Vehicle to Shift to ” is shown
If the P position switch is pressed while driving, the shift po sition is changed
to N and the message is shown. ( P. 341)
■ If “Auto Power OFF to Conserve Battery” is shown
The power switch has been turned off by the automatic power off function.
When starting the hybrid system next time, operate the hybrid s ystem for
approximately 5 minutes to recharge the 12-volt battery.
■ If “Engine Oil Level Low Add or Replace” is displayed
The engine oil level may be low. Check the level of the engine oil, and add
engine oil if necessary. This message may be displayed if the vehicle is
stopped on a slope. Move the vehicle to a level surface and che ck if the mes-
sage disappears.
■ If “Accelerator and Brake Pedals Pressed Simultaneously” is sho wn
The accelerator and brake pedals are being depressed simultaneo usly.
( P. 316)
Release the accelerator pedal and depress the brake pedal.

7218-2. Steps to take in an emergency
PRIUS PRIME_OM_OM47E74U_(U)
8
When trouble arises
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.
6

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”.