check engine TOYOTA SIENNA 2003 XL20 / 2.G User Guide

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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” in Section 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.
Never allow anyone to ride in the
luggage compartment. It is not de-
signed for passengers. They should
ride in their seats with their seat
belts properly fastened. Otherwise,
they are much more likely to suffer
serious bodily injury, in the event
of sudden braking or a collision.
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. 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, 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, crank the engine by turning the key
to “START”. Release it when the en-
gine starts.
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” in Sec-
tion 4.
Before starting the engine How to start the engine—
(a) Before cranking
(b) Starting the engine

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NOTICE
Do not crank for more than 30 se-
conds at a time. This may overheat
the starter and wiring systems.
 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 result-
ing in tire bursts.
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.
CAUTION
Before driving off, make sure that
the parking brake is fully released
and the parking brake reminder
light is off.
Do not leave your vehicle unat-
tended while the engine is running.
Do not rest your foot on the brake
pedal while driving. It can cause
dangerous overheating, needless
wear, and poor fuel economy.
To drive down a long or steep hill,
reduce your speed and downshift.
Remember, if you ride the brakes
excessively, they may overheat and
not work properly.
Be careful when accelerating, up-
shifting, downshifting or braking on
a slippery surface. Sudden accelera-
tion or engine braking could cause
the vehicle to spin or skid.
Tips for driving in various
conditions

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Do not drive in excess of the speed
limit. Even if the legal speed limit
permits it, do not drive over 140
km/h (85 mph) unless your vehicle
has highspeed capability tires.
Driving over 140 km/h (85 mph) may
result in tire failure, loss of control
and possible injury. Be sure to con-
sult a tire dealer to determine
whether the tires on your vehicle
are highspeed capability tires or
not before driving at such speeds.
Do not continue normal driving
when the brakes are wet. If they are
wet, your vehicle will require a
longer stopping distance, and it
may pull to one side when the
brakes are applied. Also, the park-
ing brake will not hold the vehicle
securely.
Make sure you have a proper freeze
protection of engine coolant.
Your coolant must contain ethyleneglycol
type coolant for a proper corrosion
protection of aluminum components. Use
“Toyota Genuine Long Life Coolant” or
equivalent.
See 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 50C
(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. Make sure the engine oil viscosity is
suitable for the cold weather.
See Section 72 for recommended viscos-
ity. Leaving a heavy summer oil in your
vehicle during winter months may cause
harder starting. If you are not sure about
which oil to use, call your Toyota deal-
er—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.
Winter driving tips

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A safety chain must always be used
between the towing vehicle and the
trailer. Leave sufficient slack in the
chain for turns. The chain should
cross under the trailer tongue to
prevent the tongue from dropping to
the ground in case it becomes dam-
aged or separated. For correct safety
chain procedures, follow the hitch or
trailer manufacturer ’s recommenda-
tions.
CAUTION
If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.
Never tap into your vehicle’s hy-
draulic system as it would lower its
braking effectiveness.
Never tow a trailer without using a
safety chain securely attached to
both the trailer and the vehicle. If
damage occurs to the coupling unit
or hitch ball, there is danger of the
trailer wandering over into another
lane.
TIRES
Ensure that your vehicle’s tires are
properly inflated. Adjust the tire pres-
sure to the recommended cold tire
pressure indicated below. (See Section
72 and Section 8 for instructions.):
Tire pressure, kPa (kgf/cm
2 or bar, psi)
240 (2.4, 35)
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.
TRAILER LIGHTS
Trailer lights must comply with federal,
state/provincial and local regulations.
See your local recreational vehicle
dealer or rental agency for the correct
type of wiring and relays for your trail-
er. Check for correct operation of the
turn signals and stop lights each time
you hitch up. Direct splicing may dam-
age your vehicle’s electrical system
and cause a malfunction of your lights. 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
information, please refer to the
scheduled maintenance information in
the “Scheduled 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.
PRETOWING SAFETY CHECK
Check that your vehicle remains level
when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle has
an abnormal noseup or nosedown
condition, and check for improper
tongue load, overload, worn suspension
or other possible causes.
Make sure the trailer cargo is securely
loaded so that it cannot shift.

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Check that your rear view mirrors con-
form to any applicable federal, state/
provincial or local regulations. If not,
install the rear view mirrors required
for towing purpose.
TRAILER TOWING TIPS
When towing a trailer, your vehicle will
handle differently than when not tow-
ing. The three main causes of vehicle
trailer accidents are driver error, exces-
sive speed and improper trailer loading.
Keep these in mind when towing:
Before starting out, check operation of
the lights and all vehicletrailer connec-
tions. After driving a short distance,
stop and recheck the lights and con-
nections. Before actually towing a trail-
er, practice turning, stopping and back-
ing with a trailer in an area away from
traffic until you learn the feel.
Backing with a trailer is difficult and
requires practice. Grip the bottom of
the steering wheel and move your hand
to the left to move the trailer to the
left. Move your hand to the right to
move the trailer to the right. (This pro-
cedure is generally opposite to that
when backing without a trailer.) Also,
just turn the steering wheel a little at
a time, avoiding sharp or prolonged
turning. Have someone guide you when
backing to reduce the risk of an acci-
dent.
Because stopping distance may be in-
creased, vehicletovehicle distance
should be increased when towing a
trailer. For each 16 km/h (10 mph) of
speed, allow at least one vehicle and
trailer length between you and the ve-
hicle ahead. Avoid sudden braking as
you may skid, resulting in jackknifing
and loss of control. This is especially
true on wet or slippery surfaces.
Avoid jerky starts or sudden accelera-
tion.
Avoid jerky steering and sharp turns.
The trailer could hit your vehicle in a
tight turn. Slow down before making a
turn to avoid the necessity of sudden
braking.
Remember that when making a turn,
the trailer wheels will be closer than
the vehicle wheels to the inside of the
turn. Therefore, compensate for this by
making a larger than normal turning
radius with your vehicle.
Crosswinds and rough roads will ad-
versely affect handling of your vehicle
and trailer, causing sway. Pay attention
to the rear from time to time to pre-
pare yourself for being passed by large
trucks or buses, which may cause your
vehicle and trailer to sway. If swaying
happens, firmly grip the steering wheel
and reduce speed immediately but
gradually. Never increase speed. Steer
straight ahead. If you make no extreme
correction with the steering or brakes,
the vehicle and trailer will stabilize.
Be careful when passing other ve-
hicles. Passing requires considerable
distance. After passing a vehicle, do
not forget the length of your trailer and
be sure you have plenty of room be-
fore changing lanes.
In order to maintain engine braking effi-
ciency, do not use overdrive.

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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”
in Section 3 and that you have sufficient
fuel. If your vehicle is equipped with the
engine immobiliser system, also check
whether the other keys will start the en-
gine. If they work, your key may be bro-
ken. Have the key checked at your Toyota
dealer. If none of your keys work, the
system is possibly broken. Call your
Toyota dealer. (See “Keys (with engine
immobiliser system)” 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” 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 does not start, check that all the pushon connectors are tight.
(For example, connectors at the spark
plugs, ignition coil and/or distributor)
3. If the connectors are O.K., the engine may be flooded because of repeated
cranking. See “(b) Starting a flooded
engine” for further instructions. If the engine will not start, your engine
may be flooded because of repeated
cranking.
If this happens, turn the key to “START”
with the accelerator pedal held down.
Keep the key and accelerator pedal these
positions for 15 seconds and release
them. Then try starting the engine with
your foot off the accelerator pedal.
If the engine does not start after 15 se-
conds of cranking, release the key, 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.
NOTICE
Do not crank for more than 30 se-
conds at a time. This may overheat
the starter and wiring systems.
If your vehicle will not start—
(a) Simple checks
(b) Starting a flooded engine

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5. Start your engine in the normal way.After starting, run it at about 2000 rpm
for several minutes with the accelerator
pedal lightly depressed.
6. Carefully disconnect the cables in the exact reverse order: the negative cable
and then the positive cable.
7. Carefully dispose of the battery cover cloths—they may now contain sulfuric
acid.
8. If removed, replace all the battery vent plugs.
If the cause of your battery discharging is
not apparent (for example, lights left on),
you should have it checked at your Toyota
dealer. If your engine stalls while driving...
1. Reduce your speed gradually, keeping a straight line. Move cautiously off the
road to a safe place.
2. Turn on your emergency flashers.
3. Turn the ignition key to “ACC” or “LOCK”, and try starting the engine
again.
If the engine will not start, see “If your
vehicle will not start”.
CAUTION
If the engine is not running, the pow-
er assist for the brakes and steering
will not work so steering and braking
will be much harder than usual.
If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure... 1. Pull safely off the road, stop the ve- hicle and turn on your emergency
flashers. Put the transmission in “P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the radiator or reservoir, stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running and make sure the electric
cooling fan is operating. If it is not,
turn the ignition off.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
If your engine stalls while
driving If your vehicle overheats

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3. Look for obvious coolant leaks from theradiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the coolant is leaking, stop the en-gine immediately. Call a Toyota dealer
for assistance.
5. If there are no obvious leaks, check the coolant reservoir. If it is dry, add
coolant to the reservoir while the en-
gine is running. Fill it about half full.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
6. After the engine coolant temperaturehas cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You s hould have it checked as
soon as possible at your Toyota dealer. 1. Reduce your speed gradually, keeping
a straight line. Move cautiously off the
road to a safe place well away from
the traffic. Avoid stopping on the center
divider of a highway. Park on a level
spot with firm ground.
2. Stop the engine and turn on your emergency flashers.
3. Firmly set the parking brake and put the transmission in “P”.
4. Have everyone get out of the vehicle on the side away from traffic.
5. Read the following instructions thor- oughly.
CAUTION
When jacking, be sure to observe the
following to reduce the possibility of
personal injury:
Follow jacking instructions.
Do not put any part of your body
under the vehicle supported by the
jack. Otherwise, personal injury may
occur.
Do not start or run the engine while
your vehicle is supported by the
jack.
If you have a flat tire—

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If you are a skilled doityourself mechan-
ic, the Toyota service manuals are recom-
mended. Please be aware that doityour-
self maintenance can affect your warranty
coverage. See “Owner ’s Warranty Informa-
tion Booklet” or “Owner ’s Manual Supple-
ment” for the details.Listed below are the general maintenance
items that should be performed as fre-
quently as specified. In addition to check-
ing the items listed, if you notice any
unusual noise, smell or vibration, you
should investigate the cause or take your
vehicle to your Toyota dealer or a quali-
fied service shop immediately. It is recom-
mended that any problem you notice be
brought to the attention of your dealer or
the qualified service shop for their advice.
CAUTION
Make these checks only where ade-
quate ventilation can be obtained if
you run the engine.
OUTSIDE THE VEHICLE
Items listed below should be performed
from time to time, unless otherwise
specified.
Tire pressure
Check the pressure with a gauge every
two weeks, or at least once a month. See
Section 72 for additional information.Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See Section 72 for
additional information. When checking the
tires, make sure no nuts are missing, and
check the nuts for looseness. Tighten
them if necessary.
Tire rotation
Rotate the tires according to the mainte-
nance schedule. (For scheduled mainte-
nance information, please refer to the
“Scheduled Maintenance Guide” or “Own-
er ’s Manual Supplement”.) See Section
72 for additional information.
Fluid leaks
Check underneath for leaking fuel, oil, wa-
ter or other fluid after the vehicle has
been parked for a while. If you smell fuel
fumes or notice any leak, have the cause
found and corrected immediately.
Doors and engine hood
Check that all the doors operate smoothly
and all latches lock securely. Make sure
the engine hood secondary latch secures
the hood from opening when the primary
latch is released.
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.
General maintenance