2021 TOYOTA 4RUNNER warning light

4316-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)■
The initialization operation
●Make sure to carry out initializ
ation after adjusting the tire inflation pres-
sure.
Also, make sure the tires are co ld before carrying out initialization or tire
inflation pressure adjustment.
●If you have accidentally turned the engine switch to the “LOCK” position
(vehicles without a smart key system) or off (vehicles with a s mart key
system) during initialization, it is not necessary to press the reset switch
again as initialization will rest art automatically when the engine switch
has been turned to the “ON” posi tion (vehicles without a smart key sys-
tem) or IGNITION ON mode (vehicl es with a smart key system) for the
next time.
●If you accidentally press the reset switch when initialization is not neces-
sary, adjust the tire inflation pressure to the specified level when the
tires are cold, and cond uct initialization again.
●While the position of each tire is being determined and the inf lation pres-
sures are not being displayed on the multi-information display, if the
inflation pressure of a tire drops, the tire pressure warning l ight will come
on.
■When initialization of the tire pressure warning system has fai led
●Do not move the vehicle backward during initialization. Initialization is
started again from the beginning and it may take longer than usual.
●Initialization may take longer to complete if the vehicle is driven on an
unpaved road.
When performing initialization, drive on a paved road if possib le.
Depending on the driving environment and condition of the tires , initial-
ization will be complet ed in approximately 10 to 30 minutes.
• If initialization is not complet e after driving approximately 30 minutes,
continue driving for a while.
• If initialization is not complet e after driving approximately 1 hour, park
the vehicle in a safe place for approximately 20 minutes. Then drive
straight (with occasional left a nd right turns) at approximatel y 25 mph
(40 km/h) or more
* for approximately 10 to 30 minutes.
• If initialization is still not co mplete, have the vehicle inspected by your
Toyota dealer.
*: Except when making a left/right turn
●In the following situations, the tire inflation pressure will n ot be recorded
and the system will not operate p roperly. Perform initialization again.
• When operating the tire pressure warning reset switch, the tir e pres-
sure warning light does not blink 3 times.
• After performing initialization, the tire pressure warning light blinks for
1 minute then stays on after driving for about 20 minutes.

4326-3. Do-it-yourself maintenance
4RUNNER (U)■
When ID code registration has failed
●Registration may take long time or the ID codes may not be regi
stered in
the following situations.
• When the vehicle is moved backward during registration.
Registration is started again from the beginning and it may tak e lon-
ger than usual.
• When another vehicle is running the side of the vehicle such a s in
heavy traffic.
It may take longer to detect the vehicle’ tire pressure warning valves
and transmitters.
• If tire pressure warning valves and transmitters are in the vehicle.
The ID codes may n ot be registered.
●When performing registration, drive on a paved road if possible .
Depending on the driving environment and condition of the tires, regis-
tration will be complet ed in approximately 10 to 30 minutes.
• If registration is not complete after driving approximately 30 minutes,
continue driving for a while.
• If registration is not complete after driving approximately 1 hour, park
the vehicle in a safe place for approximately 20 minutes. Then drive
straight (with occasional left and right turns) at approximatel y 40 km/h
(25 mph) or more
* for approximately 10 to 30 minutes.
If registration is still not comp lete, have the vehicle inspected by your
Toyota dealer.
*: Except when making a left/right turn
●When the tire pressure warning light does not blink slowly 3 ti mes, the
ID code will not be registered and the system will not operate properly.
Perform registration again.
■When registering ID codes
●Initialize the tire pressure war ning system after ID code regis tration. Ini-
tialization is disable d if the system was initialized before re gistration.
●After ID code registration, the tires are hot by driving. Initi alize the tire
pressure warning system af ter the tires become cold.
■Canceling the change wheel set mode
●If turning the engine switch to the “LOCK” position (vehicles w ithout a
smart key system) or off (vehicles with a smart key system) whe n in the
change wheel set mode before driving, the change wheel set mode is
canceled.
●After driving when in the change wheel set mode, the change whe el set
mode cannot be canceled. To cancel the mode, perform the proced ure
for ID code registration again and turn the engine switch to th e “LOCK”
position (vehicles without a smart key system) or off (vehicles with a
smart key system ) before driving.
●If the change wheel set mode is canceled, the ID codes that hav e
already been registered are commu nicated. When communication is fin-
ished, the tir e pressure warning light will turn off.

4346-3. Do-it-yourself maintenance
4RUNNER (U)
WARNING
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as
dangerous handling characteristics, which may lead to an accide nt
resulting in death o r serious injury.
●Do not mix tires of different ma kes, models or tread patterns.
Also, do not mix tires of re markably different treadwear.
●Do not use tire sizes other th an those recommended by Toyota.
●Do not mix differently constructed tires (radial, bias-belted o r bias-ply
tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have b een used on another vehicle.
Do not use tires if you do not kn ow how they were used previous ly.
■When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first
adjusting the tire inflation pressure to the specified level. O therwise, the
tire pressure warning light may not come on even if the tire in flation
pressure is low, or it may come on when the tire inflation pres sure is
actually normal.

4486-3. Do-it-yourself maintenance
4RUNNER (U)
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been repla ced, a bulb may
need replacement. ( P. 449)
● If the replaced fuse blows again, have the vehicle inspected by your Toyota
dealer.
■ If there is an overload in a circuit
The fuses are designed to blow, protecting the wiring harness f rom damage.
WARNING
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failure to do so may cause damage to the vehicle, and possibly a fire or
injury.
● Never use a fuse of a higher amperage rating than that indicate d, or use
any other object in place of a fuse.
● Always use a genuine Toyota fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
● Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired b y your
Toyota dealer as soon as possible.

4596-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)■
Replacing the following bulbs
If any of the lights listed below has burnt out, have it replac
ed by
your Toyota dealer.
● Headlight low beams (if equipped)
● Headlight low/high beams (if equipped)
● Fog lights
● Side turn signal lights
● Stop/tail lights
● Rear side marker lights
● High mounted stoplight
● Outer foot lights (if equipped)
■LED light bulbs
The headlight low beams (if equipped), headlight low/high beams (if
equipped), fog lights, side turn signal lights, stop/tail light s, rear side marker
lights, high mounted stoplight and outer foot lights consist of a number of
LEDs. If any LEDs burn out, take your vehicle to your Toyota de aler to have
the light replaced.
■ Condensation build-up on the inside of the lens
Temporary condensation build-up on the inside of the lens does not indicate a
malfunction. Contact your Toyota dealer for more information in the following
situations:
● Large drops of water have built up on the inside of the lens.
● Water has built up inside the lens.
WARNING
■Replacing light bulbs
● Turn off the lights. Do not attempt to replace the bulb immedia tely after
turning off the lights.
The bulbs become very hot and may cause burns.
● Do not touch the glass portion of the light bulb with bare hands. When it is
unavoidable to hold the glass portion, use and hold with a clea n dry cloth
to avoid getting moisture and oils on the bulb.
Also, if the bulb is scratched or dropped, it may blow out or crack.
● Fully install light bulbs and any parts used to secure them. Fa ilure to do so
may result in heat damage, fire, or water entering the headligh t unit. This
may damage the headlights or cause condensation to build up on the lens.
■ To prevent damage or fire
● Make sure bulbs are fully seated and locked.
● Check the wattage of the bulb before installing to prevent heat damage.

461
When trouble arises7
4RUNNER (U)7-1. Essential information
Emergency flashers .......... 462
If your vehicle has to be stopped in an
emergency ...................... 463
If the vehicle is trapped in rising water ..................... 465
7-2. Steps to take in an emergency
If your vehicle needs to be towed .............................. 466
If you think something is wrong .............................. 472
Fuel pump shut off system ............................ 473
If a warning light turns on or a warning buzzer
sounds ............................ 474
If a warning message is displayed......................... 484
If you have a flat tire.......... 489
If the engine will not start ................................. 504
If you cannot operate back door opener ............ 506
If the electronic key does not operate properly
(vehicles with a smart
key system)..................... 507
If the vehicle battery is discharged ...................... 510
If your vehicle overheats ........................ 514
If the vehicle becomes stuck ............................... 517

4747-2. Steps to take in an emergency
4RUNNER (U)
If a warning light turns on or a war ning
buzzer sounds
Calmly perform the following actions if any of the warning ligh ts
comes on or flashes. If a light comes on or flashes, but then
goes off, this does not necessarily indicate a malfunction in the
system. However, if this continues to occur, have the vehicle
inspected by your Toyota dealer.
Warning light and w arning buzzer list
Warning lightWarning light/Details/Actions
(U.S.A.)
(Canada)
Brake system warning li ght (warning buzzer)
• Low brake fluid
• Malfunction in the brake system
This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is
fully released the system is operating normally.
 Immediately stop the vehicle in a safe place and
contact your Toyota dealer. Continuing to drive
the vehicle may be dangerous.
High coolant temperature warning light (warning
buzzer)
*4
Indicates that the engine coolant temperature is too
high
 Immediately stop the vehicle in a safe place.
Handling method ( P. 514)
Charging system warning light
Indicates a malfunction in the vehicle’s charging sys-
tem
 Immediately stop the vehicle in a safe place and
contact your Toyota dealer.
Low engine oil pressure warning light*4
Indicates that the engine oil pressure is too low
 Immediately stop the vehicle in a safe place and
contact your Toyota dealer.

4757-2. Steps to take in an emergency
7
When trouble arises
4RUNNER (U)(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The emission control system;
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission control sys-
tem
 Have the vehicle inspected by your Toyota dealer
immediately.
SRS warning light
Indicates a malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system;or
• The seat belt pretensioner system
 Have the vehicle inspected by your Toyota dealer
immediately.
(U.S.A.)
(Canada) ABS warning light
Indicates a malfunction in:
• The ABS; or
• The brake assist system
 Have the vehicle inspected by your Toyota dealer
immediately.
Slip indicator
Indicates a malfunction in:
• The VSC system;
• Trailer Sway Control system;
• The TRAC system;
• The active traction control system;
• The AUTO LSD system;
• The downhill assist control system;
• The hill-start assist control system; or
• The Crawl Control system
 Have the vehicle inspected by your Toyota dealer
immediately.
(Flashes rapidly)
Rear differential lock indi cator light (if equipped)
Indicates a malfunction in the rear differential lock sys-
tem
 Have the vehicle inspected by your Toyota dealer
immediately.
Warning lightWarning light/Details/Actions