2021 TOYOTA PRIUS traction control

512
PRIUS_OM_OM47E09U_(U)
6-3. Do-it-yourself maintenance
Do-it-yourself ser vice precautions
If you perform maintenance by yourself, be sure to follow the
correct procedure as given in these sections.
ItemsParts and tools
12-volt battery
condition
(  P. 5 2 4 )•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
( P. 5 2 8 )
• SAE J1703 or FMVSS No.116 DOT 3 or SAE J1704
or FMVSS No.116 DOT 4 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power
control unit cool-
ant level
( P. 5 2 2 )
• “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
For the U.S.A.:
“Toyota Super Long Life Coolant” is pre-mixed with
50% coolant and 50% deionized water.
For Canada:
“Toyota Super Long Life Coolant” is pre-mixed with
55% coolant and 45% deionized water.
• Funnel (used only for adding coolant)
Engine oil level
( P. 5 1 9 )• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses ( P. 563)• Fuse with same amperage rating as original
Hybrid battery
(traction battery)
air intake vent
( P. 5 5 1 )• Vacuum cleaner, etc.
• Phillips screwdriver
Light bulbs
( P. 5 6 8 )
• Bulb with same number and wattage rating as origi-
nal
• Phillips screwdriver
• Flathead screwdriver• Wrench
Radiator and con-
denser ( P. 524)

6077-2. Steps to take in an emergency
PRIUS_OM_OM47E09U_(U)
7
When trouble arises
■If “Shift System Malfunction See Owner’s Manual” is shown
Indicates a malfunction in the shift control system. Immediatel y have the sys-
tem inspected by your Toyota dealer.
The system may not operate properly.
■ If “Low 12-Volt Battery Apply Parking Brake Securely While Park ing See
Owner’s Manual” is shown
Indicates that the 12-volt battery charge is insufficient. Char ge or replace the
12-volt battery.
● When the message is shown, the hybrid system may not start or t he shift
position may not be changed normally. (Coping method: P. 609)
● After charging the 12-volt battery, the message may not go off until the shift
position is changed from P.
■ If “Shifting Unavailable Low 12-Volt Battery See Owner’s Manual ” is
shown
Indicates that the shift position cannot be changed because the voltage of the
12-volt battery drops. Charge or replace the 12-volt battery.
(Coping method in the case the 12-volt battery is discharged: P. 650)
■ If “Hybrid System Overheated. Reduced Output Power.” is shown
The message may be shown when driving under severe operating co nditions.
(For example, when driving up a long steep hill or driving up a steep hill in
reverse.)
Coping method: P. 656
■ If “Maintenance required for Traction battery cooling parts See owner’s
manual” is shown
The filter may be clogged, the air intake vent may be blocked or there may be
a gap in the duct.
● If the air intake vent is dirty, refer to P. 551 for information on how to clean
the air intake vent.
● If the message is shown when the air intake vent is not dirty, have the vehi-
cle inspected by your Toyota dealer.
■ If “Traction Battery Needs to be Protected Refrain From the Use of
Position” is shown
This message may be displayed when the shift position is in N.
As the hybrid battery (traction battery) can not be charged when the shift
position is in N, shift the shift position to P when the vehicle is stopped.
■ If “Traction Battery Needs to be Protected Shift into to Resta rt” is
shown
This message is displayed when the hybrid battery (traction battery) charge
has become extremely low because the vehicle has been left with the N shift
position selected for a certain amount of time.
When operating the vehicle, shift to P and restart the hybrid s ystem.

645
PRIUS_OM_OM47E09U_(U)
7
When trouble arises
7-2. Steps to take in an emergency
If the hybrid system will not start
One of the following may be the cause of the problem:
● The electronic key may no t be functioning properly.
* ( P. 647)
● There may not be sufficient f uel in the vehicle’s tank.
Refuel the vehicle. ( P. 90)
● There may be a malfunction in the immobilizer system.
* ( P. 9 5 )
● There may be a malfunction i n the shift control system.
*
(  P. 249, 609)
● The hybrid system may be malfunc tioning due to an electrical prob-
lem such as electronic key battery depletion or a blown fuse. H ow-
ever, depending on the type of malfunction, an interim measure is
available to start the hybrid system. ( P. 646)
● There is a possibility that the t emperature of the hybrid battery
(traction battery) is extremely low (approximately below -22°F
[-30°C]). ( P. 90, 248)
*: It may not be possible to shift the shift position other than P.
One of the following may be the cause of the problem:
● The 12-volt battery may be discharged. ( P. 650)
● The 12-volt battery terminal connections may be loose or corrod ed.
(  P. 524)
Reasons for the hybrid system not starting vary depending on
the situation. Check the followi ng and perform the appropriate
procedure:
The hybrid system will not start even though the correct starting
procedure is being followed. ( P. 245)
The interior lights and headlights are dim, or the horn does no t
sound or sounds at a low volume.

682
PRIUS_OM_OM47E09U_(U)
8-1. Specifications
This information has been prepared in accordance with regulations
issued by the National Highway Tr affic Safety Administration of the
U.S. Department of Transportation.
It provides the purchasers and/or prospective purchasers of Toyota
vehicles with info rmation on uniform ti re quality grading.
Your Toyota dealer will help answer any questions you may have as
you read this information.
■DOT quality grades
All passenger vehicle tires must conform to Federal Safety Requ ire-
ments in addition to these grades. Quality grades can be found
where applicable on the tire sidewall between tread shoulder an d
maximum section width.
For example: Treadwear 200 Traction AA Temperature A
■Treadwear
The treadwear grade is a comparative rating based on the wear
rate of the tire when tested under controlled conditions on a s peci-
fied government t est course.
For example, a tire graded 150 would wear one and a half (1 - 1 /2)
times as well on the governmen t course as a tire graded 100.
The relative performance of tires depends upon the actual condi -
tions of their use. Performance ma y differ significantly from the norm
due to variations in driving habits, service practices and diff erences
in road characteristics and climate.
■Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C ,
and they represent the tire’s ability to stop on wet pavement a s
measured under controlled conditions on specified government te st
surfaces of asphalt and concrete.
A tire marked C may have p oor traction performance.
Warning: The traction grade assigned to this tire is based on b raking
(straight ahead) traction tests and does not include cornering (turn-
ing) traction.
Uniform Tire Quality Grading

725Alphabetical index
PRIUS_OM_OM47E09U_(U)
Anti-lock brake system (ABS) ...................................... 420
Function ................................ 420
Warning light ......................... 593
Approach warning ................... 336
Armrest ..................................... 486
Assist grips .............................. 487
Audio input
*
Audio system*
Automatic air conditioning system ............................ 436, 446
Air conditioning eco mode .......................... 439, 449
Air conditioning filter ............. 548
Automatic air conditioning
system ....... ................. 436, 446
Eco score (A/C score)........... 148
Front seat concentrated
airflow mode
(S-FLOW) ................... 438, 448
Automatic door locking and unlocking systems ................ 188
Automatic High Beam
(AHB) ...................................... 268
Automatic light control system .................................... 266
AUX port
*
Auxiliary box ............................ 465 Back door ................................. 191
Back-up light............................ 569
Replacing light bulb .............. 572
Wattage ................................ 674
Battery (12-volt battery) .......... 524
Battery checking ................... 524
If the 12-volt battery is discharged.......................... 650
Preparing and checking before winter ...................... 430
Replacing.............................. 653
Warning light......................... 592
Battery (traction battery) .......... 88 Air intake vent ......................... 89
Location .................................. 88
Specification ......................... 667
Blind Spot Monitor (BSM) ....... 349
Blind Spot Monitor function............................... 354
Rear Cross Traffic Alert
function............................... 357
Bluetooth
®*
B
*: Refer to “NAVIGATION SYSTEM OWNER’S MANUAL” or “MULTIMEDIA OWNER’S MANUAL”.

727Alphabetical index
PRIUS_OM_OM47E09U_(U)
CleaningAluminum wheels.................. 497
Exterior ................................. 496
Front camera ........................ 291
Hybrid battery (traction
battery) air intake vent ........ 551
Interior................................... 502
Radar sensor ........................ 290
Seat belts .............................. 503
Water-repellent coating......... 497
Clock ........................................... 98
Adjustment ............................ 103
Coat hooks ............................... 486
Combination meter .................... 98 Clock adjustment .................. 103
Main display .......................... 115
Multi-information display ....... 124
Warning lights and indicators ............................ 107
Condenser ................................ 524
Console box ............................. 462
Consumption screen ....... 165, 172
Coolant ..................................... 522
Capacity ................................ 670
Checking ............................... 522
Preparing and checking before winter....................... 430
Cooling system ........................ 522 Engine overheating ............... 656
Hybrid system overheating ... 658
Cruise control Cruise control........................ 342
Dynamic radar cruise control with full-speed range .......... 326
Cup holders.............................. 463
Curtain shield airbags ............... 35
Customizable features ............ 690 Daytime running light
system.................................... 266
Deck board ............................... 467
Defogger Outside rear view
mirrors ........................ 440, 450
Rear window ................. 440, 450
Windshield .................... 440, 450
Dimension ................................ 664
Dinghy towing.......................... 244
Display BSM (Blind Spot Monitor) ..... 349
Drive information .................. 126
Dynamic radar cruise control with full-speed range .......... 326
Energy monitor ..... 127, 165, 172
Head-up display.................... 158
Intuitive parking assist .......... 363
LTA (Lane Tracing Assist) .... 316
Main display.......................... 115
Multi-information display ....... 124
Parking Support Brake function............................... 379
RCTA detection screen ........ 349
RSA (Road Sign Assist) ....... 323
S-APGS (Simple Advanced Parking Guidance
System) .............................. 390
Pre-collision warning ............ 297
Trip information..................... 119
Warning messages ............... 603
Do-it-yourself maintenance .... 512
Door courtesy lights ............... 458 Location ................................ 458
Wattage ................................ 674D
*: Refer to “MULTIMEDIA OWNER’S MANUAL”.

728Alphabetical index
PRIUS_OM_OM47E09U_(U)
DoorsAutomatic door locking and
unlocking system ................ 188
Back door.............................. 191
Door glasses ......................... 218
Door lock............................... 185
Open door warning buzzer ... 189
Open door warning light........ 594
Outside rear view mirrors...... 216
Rear door child-protectors .... 188
Side doors............................. 185
Side windows ........................ 218
Drive information ..................... 126
Drive-Start Control .................. 230
Driver’s seat belt reminder light......................................... 595
Driving ...................................... 228
Break-in tips .......................... 230
Correct driving posture ........... 28
Driving in the rain .................. 229
Driving mode select switch ... 347
Hybrid vehicle driving tips ..... 427
Procedures ........................... 228
Winter drive tips .................... 430
Dynamic radar cruise control with full-speed range ............ 326
ECB (Electronically Controlled Brake System) .... 420
Eco drive mode ........................ 347
EDR (Event data recorder) ........ 11
Electric motor (traction motor) Location .................................. 84
Specification ......................... 667 Electric Power Steering
(EPS) ...................................... 421
Function ................................ 421
Warning light......................... 593
Electronic key .......................... 180
Battery-saving function ......... 198
If the electronic key does not operate properly ........... 647
Replacing the battery............ 560
Electronically Controlled Brake System (ECB) ............. 420
Emergency flashers ................ 580
Emergency tire puncture repair kit ................................. 613
Emergency, in case of If a warning buzzer sounds... 592
If a warning light turns on ..... 592
If a warning message is displayed ............................ 603
If the 12-volt battery is
discharged.......................... 650
If the electronic key does not operate properly ........... 647
If the hybrid system will not start .............................. 645
If the vehicle becomes stuck ................................... 661
If the vehicle is trapped in rising water ......................... 582
If you have a flat tire ..... 611, 631
If you lose your keys ..... 181, 184
If you think something is wrong .............................. 591
If your vehicle has to be stopped in an emergency ... 581
If your vehicle needs to be
towed.................................. 584
If your vehicle overheats....... 656
Energy monitor ........ 127, 165, 172
E

730Alphabetical index
PRIUS_OM_OM47E09U_(U)
Front turn signal lights ........... 261Replacing light bulbs............. 577
Turn signal lever ................... 261
Fuel ........................................... 675 Capacity ................................ 667
Fuel gauge ............................ 116
Information ............................ 675
Refueling............................... 283
Type ...................................... 667
Warning light ......................... 594
Fuel consumption............ 133, 170
Fuel filler door.......................... 283
Opener .................................. 285
Refueling............................... 283
When the fuel filler door cannot be opened............... 286
Fuses ........................................ 563
Garage door opener ................ 488
Glove box ................................. 462
Hands-free system (for
cellular phone)
*
Head restraints ........................ 209
Head-up display ....................... 158
Headlights ................................ 263 AHB (Automatic High Beam) ................................. 268
Headlight aim ................ 566, 716
Light switch ........................... 263
Replacing light bulbs............. 577
Heated steering wheel............. 456
Heaters Automatic air conditioning
system ....... ................. 436, 446
Heated steering wheel .......... 456
Outside rear view mirrors ........................ 440, 450
Seat heaters ......................... 456 High coolant temperature
warning light.......................... 594
High mounted stoplight Replacing.............................. 577
High-voltage components ........ 88
Hill-start assist control ........... 421
Hood ......................................... 515
Hooks
Cargo hooks ......................... 468
Coat hooks ........................... 486
Grocery bag hook ................. 469
Retaining hooks (floor mat) .... 26
Horn .......................................... 212
Hybrid battery (tr action battery)
Air intake vent ......................... 89
Location .................................. 88
Specification ......................... 667
Hybrid battery (traction battery) air intake vent............ 89 Cleaning ............................... 551
Hybrid system............................ 84 Brake Override System ........ 229
Drive-Start Control ................ 230
Emergency shut off system .... 89
Energy monitor/consumption
screen ................ 127, 165, 172
EV drive mode ...................... 252
High voltage components ....... 88
Hybrid System Indicator ....... 129
Hybrid system precautions ..... 88
Hybrid vehicle driving tips ..... 427
If the hybrid system will not start .................................... 645
Overheating .......................... 656
Power switch ........................ 245
Regenerative braking ............. 86
Starting the hybrid system .... 245
Vehicle proximity notification system .......... ..................... ... 85
Hybrid System Indicator ......... 129
Hybrid transmission................ 255
G
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