2006 TOYOTA SIENNA engine overheat

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To turn on the seat heater, move the
dial upward (“L” dial for the left front
seat or “R” dial for the right front
seat). At this time, the indicator light
will illuminate to indicate the seat heat-
er is operating.
Move the dial upward or downward to ad-
just to the desired temperature.
To turn it off, move the dial downward
until it stops.
When the seat heater is not in use, move
the dial fully downward.
The key must be in the “ON” position to
operate seat heaters.
CAUTION
Occupants must use caution when op-
erating the seat heater because it
may make them feel too hot or cause
burns at low temperatures (erythema,
varicella). Use extra caution for;
Babies, small children, elderly per-
sons, sick persons or persons with
physical disabilities
Persons who have sensitive skin
Persons who are exhausted
Persons who have taken alcohol or
drugs which induce sleep (sleeping
drug, cold remedy, etc.)
To prevent the seat from overheating,
do not use the seat heater with a
blanket, cushion, or other insulating
objects which cover the seat.
NOTICE
 Do not put unevenly weighed ob-
jects on the seat and do not stick
sharp objects (needles, nails, etc.)
into the seat.
 When cleaning the seats, do not
use organic substances (paint thin-
ner, benzine, alcohol, gasoline,
etc.). They may damage the heater
and seat surface.
 To prevent the battery from being
discharged, turn the switch off
when the engine is not running.
Seat heaters

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The gauge indicates the engine coolant
temperature when the ignition switch is
on. The engine operating temperature
will vary with changes in weather and
engine load.
If the needle moves into the red zone,
your engine is too hot. If your vehicle
overheats, stop your vehicle and allow the
engine to cool.
Your vehicle may overheat during severe
operating conditions, such as:
Driving up a long hill on a hot day.
Reducing speed or stopping after high
speed driving.
Idling for a long period with the air
conditioning on in stop−and− go traffic.
Towing a trailer.
NOTICE
Do not remove the thermostat in
the engine cooling system as this
may cause the engine to overheat.
The thermostat is designed to con-
trol the flow of coolant to keep the
temperature of the engine within
the specified operating range.
 Do not continue driving with an
overheated engine. See “If your ve-
hicle overheats” on page 420 in
Section 4.
The tachometer indicates engine speed
in thousands of rpm (revolutions per
minute). Use it while driving to select
correct shift points and to prevent en-
gine lugging and overrevving.
Driving with the engine running too fast
causes excessive engine wear and poor
fuel economy. Remember, in most cases
the slower the engine speed, the greater
the fuel economy.
NOTICE
Do not let the indicator needle get
into the red zone. This may cause
severe engine damage.
Tachometer

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Vehicles with cruise control or dynamic
laser cruise control—When the cruise con-
trol is being used, even if you downshift
from “D” to “4”, engine braking will not be
enabled because the cruise control is not
cancelled.
For ways to decrease the vehicle speed,
see “Cruise control” on page 213 or “Dy-
namic laser cruise control” on page 216
in this Section.
CAUTION
Be careful when downshifting on a
slippery surface. Abrupt shifting
could cause the vehicle to skid or
spin.
(d) Using “3”, “2” and “L” positions
The “3”, “2” and “L” positions are used for
strong engine braking as described pre-
viously.
With the selector lever in ”3”, “2” or “L”,
you can start the vehicle in motion as
with the lever in “D”.
With the selector lever in “3” or “2”, the
vehicle will start in first gear and automat-
ically shift to third gear or second gear.With the selector lever in “L”, the trans-
mission is engaged in first gear.
NOTICE

Be careful not to overrev the en-
gine. Watch the tachometer to keep
engine rpm from going into the red
zone. The approximate maximum al-
lowable speed for each position is
given below for your reference:
Twowheel drive models “3” 90 km/h (56 mph) . . . . . . . . . .
“2” 58 km/h (36 mph) . . . . . . . . . .
“L” 32 km/h (20 mph) . . . . . . . . . .
Allwheel drive models “3” 87 km/h (54 mph) . . . . . . . . . .
“2” 56 km/h (35 mph) . . . . . . . . . .
“L” 30 km/h (19 mph) . . . . . . . . . .
 Do not continue hill climbing or
hard towing for a long time in the
“3”, “2” or “L” position. This may
cause severe automatic transmis-
sion damage from overheating. To
prevent such damage, “4” position
should be used in hill climbing or
hard towing.

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(e) Backing up1. Bring the vehicle to a complete stop.
2. With the brake pedal held down with your foot, shift the selector lever to the
“R” position.
NOTICE
Never shift into reverse while the ve-
hicle is moving.
Vehicles with rear view monitor system—
When the selector lever is shifted into “R”
position with the ignition switch in the
“ON” position, rear view monitor system
will activate. For instructions, see “Rear
view monitor system” on page 348 in Sec-
tion 1 −10.
(f) Parking 1. Bring the vehicle to a complete stop.
2. With the brake pedal pressed down, fully depress the parking brake pedal
to apply the parking brake securely.
3. With the brake pedal pressed down, shift the selector lever to the “P” posi-
tion.
CAUTION
Never attempt to move the selector
lever into “P” position under any cir-
cumstances while the vehicle is mov-
ing. Serious mechanical damage and
loss of vehicle control may result.
(g) Good driving practice
If the transmission repeatedly shifts up
and down between fourth gear and
overdrive when climbing a gentle slope,
shift the selector lever to the “4” posi-
tion. Be sure to shift the selector lever
to the “D” position immediately after-
ward.
When towing a trailer, in order to main-
tain engine braking efficiency, do not
use “D” position.
CAUTION
Always keep your foot on the brake
pedal while stopped with the engine
running. This prevents the vehicle
from creeping.
NOTICE
Always use the brake pedal or the
parking brake to hold the vehicle on
an upgrade. Do not attempt to hold
the vehicle using the accelerator ped-
al, as this can cause the transmission
to overheat.
(h) If you cannot shift the selector le- ver out of “P” position
If you cannot shift the selector lever from
the “P” position even though the brake
pedal is depressed, use the shift lock
override button. For instructions, see “If
you cannot shift automatic transmission
selector lever” on page 439 in Section 4.

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The threeway catalytic converter is an
emission control device installed in the
exhaust system.
The purpose is to reduce pollutants in the
exhaust gas.
CAUTION
Keep people and combustible mate-
rials away from the exhaust pipe
while the engine is running. The
exhaust gas is very hot.
Do not drive, idle or park your ve-
hicle over anything that might burn
easily such as grass, leaves, paper
or rags.
NOTICE
A large amount of unburned gases
flowing into the threeway catalytic
converter may cause it to overheat
and create a fire hazard. To prevent
this and other damage, observe the
following precautions:
Use only unleaded gasoline.
 Do not drive with an extremely low
fuel level; running out of fuel could
cause the engine to misfire, creat-
ing an excessive load on the three
way catalytic converter.
 Do not allow the engine to run at
idle speed for more than 20 min-
utes.
 Avoid racing the engine.
 Do not pushstart or pullstart your
vehicle.
 Do not turn off the ignition while
the vehicle is moving.
Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel system could cause an ex-
tremely high threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway cata-
lytic converter and the entire emis-
sion control system operate proper-
ly, your vehicle must receive the
periodic inspections required by the
Toyota Maintenance Schedule. For
scheduled maintenance information,
refer to the “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.
Threeway catalytic converters

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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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Because stopping distance may be in-
creased, following 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 vehicle ahead.
Avoid sudden braking as you may skid,
resulting in jackknifing and loss of con-
trol. 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 place the transmission
in “D”.
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85 F]) when going up a long or
steep grade with a trailer. If the engine
coolant temperature gauge indicates
overheating, immediately turn off the air
conditioning (if in use), pull off the road
and stop in a safe spot. Refer to “If
your vehicle overheats” on page 420 in
Section 4.
Always place wheel blocks under both
the vehicle and trailer wheels when
parking. Apply the parking brake firmly.
Put the transmission in “P”. Avoid park-
ing on a slope with a trailer, but if it
cannot be avoided, do so only after
performing the following:
1. Apply the brakes and hold.
2. Have someone place wheel blocks un- der both the vehicle and trailer wheels.
3. When the wheel blocks are in place, release your brakes slowly until the
blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into “P” and turn off the engine.

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When restarting out after parking on a
slope:
1. With the transmission in “P”, start the engine. Be sure to keep the brake ped-
al depressed.
2. Shift into gear.
3. Release the parking brake and brake pedal and slowly pull or back away
from the wheel blo cks. Stop and apply
your brakes.
4. Have someone retrieve the blo cks.CAUTION
Do not exceed 72 km/h (45 mph) or
the posted towing speed limit,
whichever is lower. Because insta-
bility (swaying) of a towing vehicle
trailer combination usually in-
creases as the speed increases, ex-
ceeding 72 km/h (45 mph) may
cause loss of control.
Slow down and downshift before
descending steep or long downhill
grades. Do not make sudden down-
shifts.
Avoid holding the brake pedal down
too long or too frequently. This
could cause the brakes to overheat
and result in reduced braking effi-
ciency.
Improving fuel economy is easy—just take
it easy. It will help make your vehicle last
longer, too. Here are some specific tips
on how to save money on both fuel and
repairs:
Keep your tires inflated at the cor-
rect pressure. Underinflation causes
tire wear and wastes fuel. See page
471 in Section 7 −2 for instructions.
Do not carry unneeded weight in
your vehicle. Excess weight puts a
heavier load on the engine, causing
greater fuel consumption.
Avoid lengthy warmup idling. Once
the engine is running smoothly, begin
driving—but gently. Remember, howev-
er, that on cold winter days this may
take a little longer.
Put the selector lever into the “D”
when engine braking is not required.
Driving with the selector lever in “4”
will reduce the fuel economy. (For de-
tails, see “Automatic transmission” on
page 199 in Section 1 −7.)
Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
How to save fuel and make
your vehicle last longer