2004 TOYOTA SIENNA engine overheat

04 SIENNA_U (L/O 0408)
94
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
To turn on the seat heater, move the
dial upward (“L” dial for the left front
seat and “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 delicate 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

04 SIENNA_U (L/O 0408)
164
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Low fuel level
warning light
The gauge indicates the approximate
quantity of fuel remaining in the tank
when the ignition switch is on.
Nearly full—Needle at “F”
Nearly empty—Needle at “E”
It is a good idea to keep the tank over
1/4 full.
The needle moves when braking, acceler-
ating or making turns. This is caused by
the movement of the fuel in the tank.
If the fuel level approaches “E” or the low
fuel level warning light comes on, fill the
fuel tank as soon as possible.On inclines or curves, due to the move-
ment of fuel in the tank, the fuel gauge
needle may fluctuate or the low fuel level
warning light may come on earlier than
usual.
If the fuel tank is completely empty, the
malfunction indicator lamp comes on. Fill
the fuel tank immediately.
The indicator lamp goes off after driving
several times. If the indicator lamp does
not go off, contact your Toyota dealer as
soon as possible.
It is not a malfunction even if the needle
of the fuel gauge returns to “E” when the
ignition switch is turned to the “START”
position.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.
Fuel gauge
Engine coolant temperature
gauge

04 SIENNA_U (L/O 0408)
165
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Idling for a long period with the air
conditioning on in stop−and− go traffic.
Towing a trailer.
It is not a malfunction even if the needle
of the engine coolant temperature gauge
returns to “C” when the ignition switch is
turned to the “START” position.
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 410 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.
It is not a malfunction even if the needle
of the tachometer returns to the bottom
position when the ignition switch is turned
to the “START” position.
NOTICE
Do not let the indicator needle get
into the red zone. This may cause
severe engine damage.
Tachometer

04 SIENNA_U (L/O 0408)
181
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
CAUTION
Be careful when downshifting on a
slippery surface. Abrupt shifting
could cause the vehicle to spin or
skid.
(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.
(e) Backing up
1. 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 337 in Sec-
tion 1 −9.
(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.

04 SIENNA_U (L/O 0408)
182
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
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 429 in Section 4. The traction control system automatical-
ly helps prevent the spinning of front
wheels when the vehicle is started or
accelerated on slippery road surfaces.
When the ignition key is turned to “ON”,
the system automatically turns on.
CAUTION
Under certain slippery road condi-
tions, full traction of the vehicle and
power against front wheels cannot be
maintained, even though the traction
control system is in operation. Do not
drive the vehicle under any speed or
maneuvering conditions which may
cause the vehicle to lose traction
control. In situations where the road
surface is covered with ice or snow,
your vehicle should be fitted with
snow tires or tire chains. Always
drive at an appropriate and cautious
speed for the present road condi-
tions.
Traction control system
(twowheel drive models)

04 SIENNA_U (L/O 0408)
369
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
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 converter

04 SIENNA_U (L/O 0408)
395
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
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

04 SIENNA_U (L/O 0408)
402
2004 SIENNA from Aug. ’04 Prod. (OM45422U)
Because stopping distance may be in-
creased, vehicle−to −vehicle 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 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
30 C [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 410 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.