2001 TOYOTA SIENNA check engine

01 SIENNA_U (L/O0008)
2272001 MY SIENNA (OM45406U)
The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by high−speed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately.
As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an express way, making it
appear that oil is excessively consumed
after driving at high speeds.IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
For detailed information on oil level check,
see “Checking the engine oil level” in Sec-
tion 7−2.
Iridium−tipped spark plugs
Your engine is fitted with iridium−tipped
spark plugs.
NOTICE
Use only iridium−tipped spark plugs
and do not adjust gaps for your en-
gine performance smooth drive−abili-
ty.
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01 SIENNA_U (L/O0008)
2282001 MY SIENNA (OM45406U)
Brake system
The tandem master cylinder brake system
is a hydraulic system with two separate
sub−systems. If either sub−system should
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping distance will be longer. Also, the
brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a
single brake system. Have your
brakes fixed immediately.
BRAKE BOOSTER
The brake booster uses engine vacuum to
power−assist the brakes. If the engine
should quit while you are driving, you can
bring the vehicle to a stop with normal
pedal pressure. There is enough reserved
vacuum for one or two stops—but no
more!
CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your reserved vacu-
um.
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
be longer.
ANTI−LOCK BRAKE SYSTEM (with
“ABS” warning light)
The anti−lock brake system is designed
to help prevent lock−up 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 anti−lock brake system
function is in action, you may feel the
brake pedal pulsating and hear a noise.
In this situation, to let the anti−lock
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 anti−lock 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 the manhole
cover, the steel plate under the construc-
tion, joints in the bridge, etc. on a rainy
day tends to activate the anti−lock brake
system.
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 is started. This means that the
anti−lock brake system is in the self−
check mode, and does not indicate a mal-
function.
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01 SIENNA_U (L/O0008)
2312001 MY SIENNA (OM45406U)
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 1−5.
Brake pad wear limit indicators
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.
Luggage stowage precautions
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.
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01 SIENNA_U (L/O0008)
2382001 MY SIENNA (OM45406U)
Before starting the engine
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.
(b) Starting the engine
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
air−fuel 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.
How to start the engine—
(a) Before cranking
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01 SIENNA_U (L/O0008)
2392001 MY SIENNA (OM45406U)
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, sharp−edged objects and
other road hazards. Failure to do so
can lead to severe tire damage result-
ing in tire bursts.
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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01 SIENNA_U (L/O0008)
2402001 MY SIENNA (OM45406U)
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 high−speed 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 high−speed 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.
Winter driving tips
Make sure you have a proper freeze
protection of engine coolant.
Your coolant must contain ethylene−glycol
type coolant for a proper corrosion
protection of aluminum components. Use
“TOYOTA Long Life Coolant” or equivalent.
See Section 7−2 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
(−58F). 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 7−3 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 7−2 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 de−icer 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.
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01 SIENNA_U (L/O0008)
2442001 MY SIENNA (OM45406U)
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
7−2 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.BREAK−IN 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.
PRE−TOWING 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 nose−up or nose−down
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.
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 vehicle−trailer 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.
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01 SIENNA_U (L/O0008)
2502001 MY SIENNA (OM45406U)
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 1−2.)
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 push−start the ve-
hicle. It may damage the vehicle or
cause a collision when the engine
starts. Also the three−way 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 push−on 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.
(b) Starting a flooded engine
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
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