2003 TOYOTA 4RUNNER check engine

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Depressing the brake pedal repeatedly
may turn on the brake system warning
light and buzzer. It is normal if the light
turns off and the buzzer stops sounding
after a few seconds.
You may hear a small sound in the engine
compartment after the engine is started or
the brake pedal is depressed repeatedly.
This is a pump pulsating sound of the
brake system, and it is not a malfunction.
CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your brake fluid
pressure reserve.
Even if the power assist is com-
pletely lost, the brakes will still
work. But you will have to push the
pedal hard, much harder than nor-
mal. And your braking distance will
increase.
ANTILOCK BRAKE SYSTEM
(with “ABS” warning light)
The antilock brake system is designed
to help prevent lockup of the wheels
during a sudden braking or braking on
slippery road surfaces. This assists in
providing directional stability and steer-
ing performance of the vehicle under
these circumstances.
Effective way to press the ABS brake
pedal: When the antilock brake system
function is in action, you may feel the
brake pedal pulsating and hear a noise.
In this situation, to let the antilock
brake system work for you, just hold the
brake pedal down more firmly. Do not
pump the brake in a panic stop. This
will result in reduced braking performan-
ce.
The antilock brake system becomes op-
erative after the vehicle has accelerated
to a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph). Depressing the brake pedal on slippery
road surfaces such as on a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the antilock brake sys-
tem.
You may hear a click or motor sound in
the engine compartment for a few seconds
when the engine is started or just after
the vehicle begins to move. This means
that the antilock brake system is in the
selfcheck mode, and does not indicate a
malfunction.
When the antilock brake system is ac-
tivated, the following conditions may
occur. They do not indicate a malfunc-
tion of the system:
You may hear the antilock brake sys-
tem operating and feel the brake pedal
pulsating and the vibrations of the ve-
hicle body and steering wheel. You
may also hear the motor sound in the
engine compartment even after the ve-
hicle is stopped.
At the end of the antilock brake sys-
tem activation, the brake pedal may
move a little forward.

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Have your Toyota dealer perform the bed-
dingdown.
BRAKE ASSIST SYSTEM
When you slam the brakes on, the
brake assist system judges as an emer-
gency stop and provides more powerful
braking for a driver who cannot hold
down the brake pedal firmly.
When you slam the brakes on, more pow-
erful braking will be applied. At this time,
you may hear a sound in the engine
compartment and feel the vibrations of the
brake pedal. This does not indicate a mal-
function.
The brake assist system becomes opera-
tive after the vehicle has accelerated to
a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
For an explanation of this system’s warn-
ing light, see “Service reminder indicators
and warning buzzers” on page 117 in Sec-
tion 15.
The brake pad wear limit indicators on
your disc brakes give a warning noise
when the brake pads are worn to where
replacement is required.
If you hear a squealing or scraping noise
while driving, have the brake pads
checked and replaced by your Toyota
dealer as soon as possible. Expensive ro-
tor damage can result if the pads are not
replaced when necessary. When stowing luggage or cargo in the
vehicle, observe the following:
Put luggage or cargo in the luggage
compartment when at all possible. Be
sure all items are secured in place.
Be careful to keep the vehicle bal-
anced. Locating the weight as far for-
ward as possible helps maintain bal-
ance.
For better fuel economy, do not carry
unneeded weight.
CAUTION
To prevent luggage or packages
from sliding forward during braking,
do not stack anything in the lug-
gage compartment higher than the
seatbacks. Keep luggage or pack-
ages low, as close to the floor as
possible.
Do not exceed 66 kg (145 lb.) of
cargo load in the luggage compart-
ment.
Do not place anything on the flat-
tened seat or it may slide forward
during braking.
Brake pad wear limit
indicators
Luggage stowage pr
ecautions

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1. Check the area around the vehicle be-
fore entering it.
2. Adjust seat position, seatback angle, seat cushion angle, head restraint
height and steering wheel angle.
3. Adjust the inside and outside rear view mirrors.
4. Lock all doors.
5. Fasten seat belts. Once you turn the ignition key to “START”
position and release it, the cranking hold
function continues to crank the engine in
“ON” position until it starts.
The function stops cranking the engine
after about 25 seconds maximum if the
engine has not started yet. When you
crank the engine again, wait a few sec-
onds and restart it.
If you hold the key in “START” position,
the function will keep cranking for about
30 seconds maximum. 1. Apply the parking brake firmly.
2. Turn off unnecessary lights and acces-
sories.
3. Put the selector lever in “P”. If you need to restart the engine while the
vehicle is moving, put the selector le-
ver in “N”. A starter safety device will
prevent the starter from operating if the
selector lever is in any drive position.
4. Depress the brake pedal and hold it to the floor until driving off.
Before starting the engine How to start the engine—
—Cranking hold function
(a) Before cranking

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Before starting the engine, be sure to fol-
low the instructions in “(a) Before crank-
ing”.
Normal starting procedure
The multiport fuel injection system/sequen-
tial multiport fuel injection system in your
engine automatically controls the proper
airfuel mixture for starting. You can start
a cold or hot engine as follows:
1. With your foot off the accelerator ped- al, turn the ignition key to “START”
position, then release it.
2. After the engine runs for about 10 se- conds, you are ready to drive.
If the weather is below freezing, let the
engine warm up for a few minutes before
driving.
If the engine stalls...
Simply restart it, using the correct proce-
dure given in normal starting.
If the engine will not start...
See “If your vehicle will not start” on page
278 in Section 4.NOTICE
 Do not race a cold engine.
 If the engine becomes difficult to
start or stalls frequently, have the
engine checked immediately.
Always slow down in gusty crosswinds.
This will allow you much better control.
Drive slowly onto curbs and, if pos-
sible, at a right angle. Avoid driving
onto high, sharpedged objects and
other road hazards. Failure to do so
can lead to severe tire damage such
as a tire burst.
Drive slowly when passing over bumps
or travelling on a bumpy r oad. Other-
wise, the impact could cause severe
damage to the tires and/or wheels.
When parking on a hill, turn the front
wheels until they touch the curb so
that the vehicle will not roll. Apply the
parking brake, and place the transmis-
sion in “P”. If necessary, block the
wheels.
Washing your vehicle or driving through
deep water may get the brakes wet. To
see whether they are wet, check that
there is no traffic near you, and then
press the pedal lightly. If you do not
feel a normal braking force, the brakes
are probably wet. To dry them, drive
the vehicle cautiously while lightly
pressing the brake pedal with the park-
ing brake applied. If they still do not
work safely, pull to the side of the road
and call a Toyota dealer for assistance.
(b) Starting the engine Tips for driving in various
conditions

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NOTICE
If driving through water, such as
when crossing shallow streams,
first check the depth of the water
and the bottom of the river bed for
firmness. Drive slowly and avoid
deep water.
 Take all necessary safety measures
to ensure that water damage to the
engine or other components does
not occur.
Water entering the engine air intake
will cause severe engine damage.
Water can wash the grease from
wheel bearings, causing rusting and
premature failure, and may also en-
ter the differentials, transmission
and transfer case, reducing the gear
oil’s lubricating qualities.
 Sand and mud that has accumulated
in brake drums and around brake
discs may affect braking efficiency
and may damage brake system com-
ponents.
Always perform a maintenance in-
spection after each day of offroad
driving that has taken you through
rough terrain, sand, mud, or water.
For scheduled maintenance informa-
tion, refer to the “Scheduled Main-
tenance Guide” or “Owner’s Manual
Supplement”.Make sure your coolant is properly pro-
tected against freezing.
Your coolant must contain ethyleneglycol
type coolant for a proper corrosion protec-
tion of aluminum components. Use “Toyota
Genuine Long Life Coolant” or equivalent.
See page 326 in Section 72 for details
about coolant type selection.
NOTICE
Do not use alcohol type antifreeze or
plain water alone.
When it is extremely cold, we recommend
to use 60% solution for your Toyota, to
provide protection down to about 50 C
(58 F). Do not use more than 70% solu-
tion for better coolant performance.
Check the condition of the battery and
cables.
Cold temperatures reduce the capacity of
any battery, so it must be in top shape
to provide enough power for winter start-
ing. Section 73 tells you how to visually
inspect the battery. Your Toyota dealer
and most service stations will be pleased
to check the level of charge.
Winter driving tips

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Make sure the engine oil viscosity is
suitable for the cold weather.
See page 324 in Section 72 for recom-
mended viscosity. Leaving a heavy sum-
mer oil in your vehicle during winter
months may cause harder starting. If you
are not sure about which oil to use, call
your Toyota dealer—he will be pleased to
help.
Keep the door locks from freezing.
Squirt lock deicer or glycerine into the
locks to keep them from freezing.
Use a washer fluid containing an anti-
freeze solution.
This product is available at your Toyota
dealer and most auto parts stores. Follow
the manufacturer ’s directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any
other substitute because it may dam-
age your vehicle’s paint.
Do not use your parking brake when
there is a possibility it could freeze.
When parking, put the transmission into
“P” and block the front wheels. Do not
use the parking brake, or snow or water
accumulated in and around the parking
brake mechanism may freeze, making it
hard to release.
Keep ice and snow from accumulating
under the fenders.
Ice and snow built up under your fenders
can make steering difficult. During bad
winter driving, stop and check under the
fenders occasionally.
Depending on where you are driving,
we recommend you carry some emer-
gency equipment.
Some of the things you might put in the
vehicle are tire chains, window scraper,
bag of sand or salt, flares, small shovel,
jumper cables, etc.
Your vehicle is not designed to be
dinghy towed (with four wheels on the
ground) behind a motorhome.
NOTICE
Do not tow your vehicle with four
wheels on the ground. This may
cause serious damage to your vehicle.
Dinghy towing

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TOWING CONNECTOR FOR TRAILER
LIGHTS
Your vehicle is equipped with a wire
harness stored in the rear end under
body. Some models are fitted with a
socket for trailer lights under the rear
bumper. Use either of them to connect
and operate the trailer lights. However,
the trailer lights must comply with fed-
eral, state/provincial and local regula-
tions. See your local recreational ve-
hicle dealer or rental agency for the
correct type of wiring and relays for
your trailer. Check for correct operation
of the turn signals and stop lights each
time you hitch up. Direct splicing may
damage your vehicle’s electrical system
and cause a malfunction of your lights.
The towing connector can be also con-
nected to the trailer brake and trailer
sub battery.
BREAKIN SCHEDULE
Toyota recommends that you do not
tow a trailer with a new vehicle or a
vehicle with any new power train com-
ponent (engine, transmission, differen-
tial, wheel bearing, etc.) for the first
800 km (500 miles) of driving. MAINTENANCE
If you tow a trailer, your vehicle will
require more frequent maintenance due
to the additional load. For this informa-
tion, please refer to the scheduled
maintenance information in the “Sched-
uled Maintenance Guide” or “Owner ’s
Manual Supplement”.
Retighten all fixing bolts of the towing
ball and bracket after approximately
1000 km (600 miles) of trailer driving.
CONNECTING A TRAILER (models with
rear height control air suspension)
Stop your vehicle and a trailer in line and
perform the following: 1. Put the rear height control air suspen- sion in the “LO” (low) mode. Turn the
ignition switch off or push the “HEIGHT
CONTROL OFF” switch to turn off the
rear height control air suspension.
2. Connect a trailer.
3. Turn the ignition switch on or push the “HEIGHT CONTROL OFF” switch to
turn on the rear height control air sus-
pension. Select the “N” (normal) mode
with the height select switch.

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Before making these checks, make sure
you have followed the correct starting pro-
cedure given in “How to start the engine”
on page 260 in Section 3 and that you
have sufficient fuel. Also, check whether
the other keys will start the engine. If
they work, your key may be broken. Have
the key checked at your Toyota dealer. If
none of your keys work, there may be a
malfunction in the immobiliser system. Call
your Toyota dealer. (See “Keys” on page
10 in Section 12.)
If the engine is not turning over or is
turning over too slowly—
1. Check that the battery terminals are tight and clean.
2. If the battery terminals are O.K., switch on the interior light.
3. If the light is out, dim or goes out when the starter is cranked, the battery
is discharged. You may try jump start-
ing. See “(c) Jump starting” on page
279 for further instructions.
If the light is O.K., but the engine still will
not start, it needs adjustment or repair.
Call a Toyota dealer or qualified repair
shop.NOTICE
Do not pull or pushstart the ve-
hicle. It may damage the vehicle or
cause a collision when the engine
starts. Also the threeway catalytic
converter may overheat and become a
fire hazard.
If the engine turns over at its normal
speed but will not start—
1. Turn the ignition key to “ACC” or “LOCK” and try starting the engine
again.
2. If the engine will not start, the engine may be flooded because of repeated
cranking. See “(b) Starting a flooded
engine” on page 278 for further instruc-
tions.
3. If the engine still will not start, it needs adjustment or repair. Call a Toyota
dealer or qualified repair shop. If the engine will not start, your engine
may be flooded because of repeated
cranking.
If this happens, turn the ignition key to
“START” with the accelerator pedal fully
depressed, and hold the key at this posi-
tion for about 30 seconds. Then the
cranking hold function stops cranking au-
tomatically, and you can try starting the
engine with your foot off the accelerator
pedal.
If the engine does not start, wait a few
minutes and try again.
If the engine still will not start, it needs
adjustment or repair. Call a Toyota dealer
or qualified repair shop for assistance.
If your vehicle will not start—
(a) Simple checks
(b) Starting a flooded engine