2003 TOYOTA SIENNA check engine light

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(a) Brake System Warning Light
This light comes on in the following cases
when the ignition key is in the “ON” posi-
tion.
When the parking brake is applied...
This light comes on for a few seconds
when the ignition key is turned to the
“ON” position even after the parking brake
is released.
When the brake fluid level is low...
CAUTION
It is dangerous to continue driving
normally when the brake fluid level is
low.
Have your vehicle checked at your
Toyota dealer in the following case:
The light does not come on even if the
parking brake is applied when the igni-
tion key is in the “ON” position.
The light does not come on even if the
ignition key is turned on with the park-
ing brake released.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If either of the following conditions
occurs, immediately stop your vehicle
at a safe place and contact your
Toyota dealer.
The light does not turn off even
after the parking brake is released
while the engine is running.
In this case, the brakes may not
work properly and your stopping
distance will become longer. De-
press the brake pedal firmly and
bring the vehicle to an immediate
stop.
The brake system warning light re-
mains on together with the “ABS”
warning light.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely un-
stable during braking.
(b) Driver’s Seat Belt Reminder Light and Buzzer
This light and buzzer remind you to
buckle up the driver’s seat belt.
Once the ignition key is turned to “ON”,
the reminder light flashes and buzzer
sounds if the driver ’s seat belt is not fas-
tened. Unless the driver fastens the belt,
the light keeps flashing and the buzzer
stops after about 4 to 8 seconds.
(c) Front Passenger ’s Seat Belt Re- minder Light
This light reminds you to buckle up the
front passenger ’s seat belt.
Once the ignition key is turned to “ON”,
the reminder light flashes if a passenger
sits in the front passenger seat and does
not fastened. However, if a front passen-
ger uses an additional seat cushion, the
light may not flash even when the seat
belt is not buckled up.
If luggage load is placed on the front
passenger seat, depending on its weight
and how it is placed on the seat, builtin
sensors in the seat cushion may detect
the pressure, causing the reminder light to
come on.

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(d) Discharge Warning Light
This light warns that the battery is being
discharged.
If it comes on while you are driving, there
is a problem somewhere in the charging
system.
The engine ignition will continue to oper-
ate, however, until the battery is dis-
charged. Turn off the air conditioning,
blower, radio, etc., and drive directly to
the nearest Toyota dealer or repair shop.
NOTICE
Do not continue driving if the engine
drive belt is broken or loose.
(e) Malfunction Indicator Lamp
This lamp comes on when the ignition
key is turned to the “ON” position and
goes off after the engine starts. This
means that the warning light system is
operating properly.
If the lamp remains on, or the lamp
comes on while driving, first check the
followings.
Empty fuel tank
If the fuel tank is empty, refuel immedi-
ately.
Loose fuel tank cap
If the fuel tank cap is loose, securely
tighten it.
These cases are temporary malfunctions.
The malfunction indicator lamp will go off
after taking several driving trips.
If the lamp will not go off even after the
several trips, contact your Toyota dealer
as soon as possible.
If the fuel tank is not empty or the fuel
tank cap is not loose...
There is a problem somewhere in the
engine, emission control system, auto-
matic transmission electrical system or
warning light system itself.
Contact your Toyota dealer as soon as
possible to service the vehicle.
Emissions Inspection and Maintenance
(I/M) programs
Your vehicle may not pass a state
emission inspection if the malfunction
indicator lamp remains on. Contact your
Toyota dealer to check your vehicle’s
emission control system and OBD
(OnBoard Diagnostics) system before
taking your vehicle for the inspection.
For details, see “Emissions Inspection and
Maintenance (I/M) programs” in Section 6. (f) Low Fuel Level Warning Light
This light comes on when the fuel level
in the tank becomes nearly empty. Fill up
the tank as soon as possible.
On inclines or curves, due to the move-
ment of fuel in the tank, the low fuel level
warning light may come on earlier than
usual.
(g) Low Engine Oil Pressure Warning
Light
This light warns that the engine oil pres-
sure is too low.
If it flickers or stays on while you are
driving, pull off the road to a safe place
and stop the engine immediately. Call a
Toyota dealer or qualified repair shop for
assistance.
The light may occasionally flicker when
the engine is idling or it may come on
briefly after a hard stop. There is no
cause for concern if it then goes out when
the engine is accelerated slightly.
The light may come on when the oil level
is extremely low. It is not designed to
indicate low oil level, and the oil level
must be checked using the level dipstick.

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CHECKING SERVICE REMINDER
INDICATORS (except the low fuel level
warning light and low windshield
washer fluid level warning light)
1. Apply the parking brake.
2. Open one of the doors. The open door warning light should
come on.
3. Close the door. The open door warning light should go
off.
4. Turn the ignition key to “ACC”. The SRS warning light should come on.
It goes off after about 6 seconds.
5. Turn the ignition key to “ON”, but do not start the engine.
All the service reminder indicators ex-
cept the open door warning light, open
power sliding door warning light and
SRS warning light should come on. The
“ABS” warning light, “VSC” warning
light, low tire pressure warning lights,
“TRAC OFF” indicator light and slip in-
dicator light go off after a few seconds. 6. Vehicles with a power sliding door sys-
tem:
Open the sliding door.
The open power sliding door warning
light should come on.
Close the sliding door.
The open power sliding door warning
light should go off.
If any service reminder indicator or warn-
ing buzzer does not function as described
above, have it checked by your Toyota
dealer as soon as possible.

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“VSC” warning light
This light warns that there is a problem
somewhere in the traction control system
or the vehicle skid control system.
The light will come on when the ignition
key is turned to “ON” and will go off after
a few seconds.
If the light comes on while driving, the
system does not work. However, as con-
ventional braking operates when applied,
there is no problem to continue your driv-
ing.In the following cases, contact your Toyota
dealer:
The warning light does not come on
after the ignition key is turned to “ON”.
The warning light remains on after the
ignition key is turned to “ON”.
The warning light comes on while driv-
ing.
The vehicle skid control system helps
provide integrated control of the sys-
tems such as an antilock brake sys-
tem, brake assist system, traction con-
trol, engine control, etc. This system
automatically controls the output of the
brakes or engine to help prevent the
vehicle from skidding when cornering
on a slippery road surface or abrupt
steering wheel operation occurs.
This system activates when the vehicle
speed is about more than 15 km/h (9
mph).
You may hear a 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 system is
in the selfcheck mode but does not indi-
cate a malfunction.
Vehicle skid control system

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The tandem master cylinder brake system
is a hydraulic system with two separate
subsystems. If either subsystem 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
powerassist 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.
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 the manhole
cover, the steel plate under the construc-
tion, joints in the bridge, etc. on a rainy
day tends to activate the antilock 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
antilock brake system is in the self
check mode, and does not indicate a mal-
function.
Brake system

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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