2004 TOYOTA SIENNA check engine light

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“VSC” warning light
This light warns that there is a problem
somewhere in the traction control system
or the vehicle stability 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 stability control system
helps provide integrated control of the
systems such as an antilock brake
system, brake assist system, traction
control, engine control, etc. This sys-
tem automatically controls the brakes
and engine to help prevent the vehicle
from skidding when cornering on a slip-
pery road surface or operating steering
wheel abruptly.
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 just after
the vehicle begins to move. This means
that the system is in the self
−check mode,
but does not indicate a malfunction.
Vehicle stability control
system

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If you need acceleration—for example,
when passing—depress the accelerator
pedal enough for the vehicle to exceed
the set speed. When you release it, the
vehicle will return to the speed set prior
to the acceleration.
CANCELLING THE PRESET SPEED
You can cancel the preset speed by:
a. Pulling the lever in the “CANCEL” di-rection and releasing it.
b.
Depressing the brake pedal.
If the vehicle speed falls below about 40
km/h (25 mph), the preset speed will auto-
matically cancel out.
If the vehicle speed drops 16 km/h (10
mph) below the preset speed, the preset
speed will also automatically cancel out.
If the preset speed automatically cancels
out other than for the above cases, have
your vehicle checked by your Toyota deal-
er at the earliest opportunity. RESETTING TO A FASTER SPEED
Push the lever up in the “+ RES” direction
and hold it. Release the lever when the
desired speed is attained. While the lever
is held up, the vehicle will gradually gain
speed.
However, a faster way to reset is to ac-
celerate the vehicle and then push the
lever down in the “− SET” direction.
RESETTING TO A SLOWER SPEED
Push the lever down in the “
− SET” direc-
tion and hold it. Release the lever when
the desired speed is attained. While the
lever is held down, the vehicle speed will
gradually decrease.
However, a faster way to reset is to de-
press the brake pedal and then push the
lever down in the “− SET” direction.
Even if you downshift from “D” to “4”, with
the cruise control on, engine braking will
not be enabled because the cruise control
is not cancelled. To decrease the vehicle
speed, reset to a slower speed with the
cruise control lever or depress the brake
pedal. If you use the brake pedal, cruise
control is cancelled. RESUMING THE PRESET SPEED
If the preset speed is cancelled by pulling
the control lever or by depressing the
brake pedal, pushing the lever up in the
“+ RES” direction will restore the speed
set prior to cancellation.
However, once the vehicle speed falls be-
low about 40 km/h (25 mph), the preset
speed will not be resumed.
CRUISE CONTROL FAILURE WARNING
If the “CRUISE” indicator light in the
instrument cluster flashes when using the
cruise control, press the “ON
−OFF” button
to turn the system off and then press it
again to turn it on.
If any of the following conditions then oc-
curs, there is some trouble in the cruise
control system.
The indicator light does not come on.
The indicator light flashes again.
The indicator light goes out after it
comes on.
If this is the case, contact your Toyota
dealer and have your vehicle inspected.

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The tandem master cylinder brake system
is a hydraulic system with two separate
sub−systems. If either sub −system s hould
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping distance will increase. 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
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 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 a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the anti −lock 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 anti −lock brake system is in the
self −check mode, and does not indicate a
malfunction.
Brake system

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1. Check the area around the vehicle be-fore entering it.
2. Adjust seat position, seatback angle, seat cushion height, 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
air
−fuel mixture for starting. You can start
a cold or hot engine as follows:
With your foot off the accelerator pedal,
crank the engine by turning the key to
“START”. Release it when the engine
starts.
Engine should be warmed up by driving,
not in idle. For warming up, drive with
smoothly turning engine until engine cool-
ant temperature is within normal range.
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
406 in Section 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, sharp −edged 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 road. 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 skid or spin.
Tips for driving in various
conditions

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TIRES
Ensure that your vehicle’s tires are
properly inflated. See page 463 in Sec-
tion 7−2 and page 491 in Section 8 for
instructions.
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 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.
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.

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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 394 in Section 3 and that you
have sufficient fuel. If your vehicle is
equipped with the engine immobilizer sys-
tem, 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 malfunc-
tion in the immobilizer system. Call your
Toyota dealer. (See “Keys (with engine
immobilizer system)” on page 10 in Sec-
tion 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” on page
407 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 406 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 key to “START”
with the accelerator pedal fully depressed.
Keep the key and accelerator pedal in
these positions for 15 seconds and re-
lease 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 the first start attempt is not success-
ful...
Check that the clamp on the jumper
cables are tight. Recharge the discharged
battery with the jumper cables connected
for several minutes and restart your en-
gine in the normal way.
If the another attempt is not successful,
the battery may be depleted. Have it ch-
ecked 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” on page 406 in this
Section.
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 engine speed does not increase when
the accelerator pedal is depressed, there
may be a problem somewhere in the elec-
tronic throttle control system.
At this time, vibration may occur. Howev-
er, if you depress the accelerator pedal
more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle
checked by your Toyota dealer as soon as
possible.
Even if the abnormality of the electronic
throttle control system is corrected during
low speed driving, the system may not be
recovered until the engine is stopped and
the ignition key is turned to “ACC” or
“LOCK” position.
CAUTION
Be especially careful to prevent erro-
neous pedal operation.
If your engine stalls while
driving If you cannot incr
ease engine
speed