check engine TOYOTA 4RUNNER 2021 (in English) Service Manual

4126-3. Do-it-yourself maintenance
4RUNNER (U)
The coolant level is satisfactory if it is between the “F” and “L” lines on
the reservoir when the engine is cold.
Reservoir cap
“F” line
“L” line
If the level is on or below the “L”
line, add coolant up to the “F” line.
(P. 514)
WARNING
■ Used engine oil
● Used engine oil contains potentially harmful contaminants which may
cause skin disorders such as inflammation and skin cancer, so c are
should be taken to avoid prolonged and repeated contact. To remove used
engine oil from your skin, wash thoroughly with soap and water.
● Dispose of used oil and filters only in a safe and acceptable manner. Do
not dispose of used oil and filters in household trash, in sewe rs or onto the
ground.
Call your Toyota dealer, service station or auto parts store fo r information
concerning recycling or disposal.
● Do not leave used engine oil within the reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■ When replacing the engine oil
● Be careful not to spill engine oil on the vehicle components.
● Avoid overfilling, or the engine could be damaged.
● Check the oil level on the dipstick every time you refill the v ehicle.
● Be sure the engine oil filler cap is properly tightened.
Engine coolant
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4136-3. Do-it-yourself maintenance
6
Maintenance and care
4RUNNER (U)
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene
glycol based non-silicate, non-amine, non-nitrite, and non-bora te coolant with
long-life hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixture of 50% coolant and 50% deion-
ized water. (Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Coolant” is a mixture of 55% coolant and 45% deion-
ized water. (Minimum temperature: -44 F [-42 C])
For more details about engine coolant, contact your Toyota deal er.
■ If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine coolant reservoir ca ps, drain cock
and water pump.
If you cannot find a leak, have your Toyota dealer test the cap and check for
leaks in the cooling system.
WARNING
■ When the engine is hot
Do not remove the engine coolant reservoir cap or the radiator cap.
(P. 515)
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■ When adding coolant
Coolant is neither plain water nor straight antifreeze. The cor rect mixture of
water and antifreeze must be used to provide proper lubrication , corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
■ If you spill coolant
Be sure to wash it off with water to prevent it from damaging p arts or paint.

4146-3. Do-it-yourself maintenance
4RUNNER (U)
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of
their condition, have your vehic le inspected by your Toyota dea ler.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
“MAX” line
“MIN” line
■Adding fluid
Make sure to check the fluid ty pe and prepare the necessary ite m.
■Refilling brake fluid
Turn the engine switch off.
Depress the brake pedal more than 40 times.
Remove the reservoir cap by hand. Add brake fluid up to the
“MAX” line.
If you do not follow the procedure above, the reservoir may over-
flow.
Radiator and condenser
WARNING
■ When the engine is hot
Do not touch the radiator or condenser as they may be hot and c ause seri-
ous injuries, such as burns.
Brake fluid
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Fluid type FMVSS No.116 DOT 3 or SAE J1703 brake fluid
Items Clean funnel
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4166-3. Do-it-yourself maintenance
4RUNNER (U)■
Fluid level
The fluid level should be within the appropriate range.
Full (when cold)
Add fluid (when cold)
Full (when hot)
Add fluid (when hot)
Hot: Vehicle has been driven around 50 mph (80 km/h) for 20 min- utes, or slightly longer in frigid temperatures. (Fluid tempera-
ture, 140°F - 175°F [60°C - 80°C]).
Cold: Engine has not been run for about 5 hours. (Room tempera- ture, 50°F - 85°F [10°C - 30°C]).
■Checking the fluid level
Make sure to check the fluid type and prepare the necessary items.
Clean all dirt off the reservoir.
Remove the cap by turni ng it counterclockwise.
Wipe the dipstick clean.
Reinstall the cap and remove it again.
Check the fluid level.
Power steering fluid
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Fluid typeAutomatic transmission fluid DEXRON® II or III
ItemsRag or paper, clean funnel (only for adding fluid)
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4466-3. Do-it-yourself maintenance
4RUNNER (U)
Turn the engine switch off.
Open the Fuse box cover.
Engine compartment
Push the tab in and lift the lid off.
Driver’s side instrument panel
Remove the lid.
Remove the fuse with the pull-
out tool.
Only type A fuse can be removed
using the pullout tool.
Checking and replacing fuses
If any of the electrical components do not operate, a fuse may
have blown. If this happens, che ck and replace the fuses as nec-
essary.
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4817-2. Steps to take in an emergency
7
When trouble arises
4RUNNER (U)■
If the tire pressure warning system is not functioning
The tire pressure warning syst
em will be disabled in the follow ing condi-
tions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and tra nsmitters
are used
●If the ID code on the tire pressure warning valves and transmit ters is not
registered in the tire pr essure warning computer
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or
higher
The tire pressure warning system may be disabled in the followi ng condi-
tions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilitie s using similar radio wave frequencies are
nearby
●If a radio set at a similar frequency is in use in the vehicle
●If a window tint that affects the radio wave signals is installed
●If there is a lot of snow or ice on the vehicle, particularly around the
wheels or wheel housings
●If non-genuine Toyota wheels are used (Even if you use Toyota wheels,
the tire pressure warning system may not work properly with som e types
of tires.)
●If tire chains are used
●Vehicles with P245/60R20 tires: If the spare tire is in a locat ion subject
to poor radio wave signal reception
●Vehicles with P245/60R20 tires : If a large metallic object whic h can
interfere with signal reception is put in the luggage compartme nt
■If the tire pressure warning light frequently comes on after bl inking
for 1 minute
If the tire pressure warning light frequently comes on after bl inking for 1
minute when the engine switch is turned on, have it checked by your
Toyota dealer.
■ Customization that can be configured at Toyota dealer
The vehicle speed linked seat belt reminder buzzer can be disab led.
(Customizable features P. 545) However, Toyota recommends that the seat
belt reminder buzzer be operational to alert the driver and fro nt passenger
when seat belts are not fastened.

4877-2. Steps to take in an emergency
7
When trouble arises
4RUNNER (U)■
If “Auto power off to co nserve battery” is shown
Power was turned off due to the automatic power off function.
Next time when starting the engine, increase the engine speed s lightly and
maintain that level for approximately 5 minutes to recharge the battery.
■ When a message that indicates the need for the shift lever oper ation is
shown
To prevent the shift lever from being operated incorrectly or t he vehicle from
moving unexpectedly, a message that requires shifting the shift lever may be
shown on the multi-information display. In that case, follow th e instruction of
the message and shift the shift lever.
■ When “Headlight System Malfuncti on Visit Your Dealer” is displayed on
the multi-information display
The following system may be malfunctioning. Have the vehicle in spected by
your Toyota dealer.
● Automatic High Beam
■ If a message that indicates the malfunction of front camera is displayed
The following systems may be suspended until the problem shown in the
message is resolved. ( P. 251, 484)
● PCS (Pre-Collision System)
● LDA (Lane Departure Alert)
● Dynamic radar cruise control
● Automatic High Beam
■ If a following message is shown, take appropriate action and co nfirm
that the message has disappeared.
*
● “Crawl Not Available Select L4 and Shift to [D] or [R] Position ”
● “Crawl Not Available Check System Operation Conditions”
*: Refer to the “Off-road Driving Owner’s Manual”.
■ If “Oil Maintenance Required Soon” is displayed (U.S.A. only)
Indicates that all maintenance according to the driven distance on the mainte-
nance schedule* should be performed soon.
Comes on approximately 4500 miles (7200 km) after the message has been
reset.
If necessary, perform maintenance. Please reset the message aft er the main-
tenance is performed. ( P. 399)
*: Refer to the separate “Scheduled Maintenance Guide” or “Owner’ s Manual
Supplement” for the maintenance interval applicable to your veh icle.

4917-2. Steps to take in an emergency
7
When trouble arises
4RUNNER (U)
WARNING
■Using the tire jack
Improper use of the tire jack may cause the vehicle to suddenly fall off
the jack, leading to death or serious injury.
●Do not use the tire jack for any purpose other than replacing t ires or
installing and removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a flat
tire.
Do not use it on other vehicles, and do not use other tire jack s for
replacing tires on this vehicle.
●Always check that the tire jack is securely set to the jack poi nt.
●Do not put any part of your body under the vehicle while it is supported
by the jack.
●Do not start or run the engine while your vehicle is supported by the
jack.
●Do not raise the vehicle w hile someone is inside.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greater than that required to
replace the tire.
●Use a jack stand if it is nece ssary to get under the vehicle.
Vehicles with Automatic running boards
●Observe the following precautions. Failure to do so may result in seri-
ous injury:
• When jacking up the vehicle, always turn the Automatic running boards switch off.
• When jacking up the vehicle, do not use an Automatic running b oard
as a jack point. The Automatic running board may break, causing
injuries.
Take particular care when lowering the vehicle to ensure that n o one
working on or near the vehicle may be injured.
■Using the jack handle
Tighten all the jack handle bol ts securely using a Phillips-hea d screw-
driver, to prevent the extension parts from coming apart unexpe ctedly.

5087-2. Steps to take in an emergency
4RUNNER (U)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Toyota emblem side
of the electronic key to the
engine switch.
When the electronic key is
detected, a buzzer sounds and the
engine switch will turn to IGNITION
ON mode.
When the smart key system is
deactivated in customization set-
ting, the engine switch will turn to
ACCESSORY mode.
Firmly depress the brake pedal and check that is displayed
on the multi-information display.
Press the engine switch shortly and firmly.
In the event that the engine still cannot be started, contact your Toyota
dealer.
■ Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when
stopping the engine.
■ Replacing the key battery
As the above procedure is a temporary measure, it is recommende d that the
electronic key battery be replaced immediately when the battery is depleted.
( P. 444)
■ Changing engine switch modes
Within 10 seconds of the buzzer sounding, release the brake ped al and press
the engine switch.
The engine does not start and modes will be changed each time t he switch is
pressed.( P. 213)
■ When the electronic key does not work properly
●Make sure that the smart key system has not been deactivated in the cus-
tomization setting. If it is off, turn the function on.
(Customizable features: P. 545)
● Check if battery-saving mode is set. If it is set, cancel the f unction.
( P. 121)
Starting the engine
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5157-2. Steps to take in an emergency
7
When trouble arises
4RUNNER (U)
Add engine coolant if neces-
sary. (P. 409)
Water can be used in an emer-
gency if engine coolant is unavail-
able.
Start the engine to check that the radiator cooling fan operate and
to check for coolant leaks from the radiator or hoses.
If the fan are not operating:
Stop the engine immediately and contact your Toyota dealer.
If the fan are operating:
Have the vehicle ins pected at the nearest Toyota dealer.
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WARNING
■When inspecting under th e 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.
● Keep hands and clothing (especially a tie, a scarf or a muffler ) away from
the fans and belts.
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● Do not loosen the radiator cap and the
coolant reservoir cap while the engine
and radiator are hot.
High temperature steam or coolant
could spray out.