2003 TOYOTA SIENNA engine

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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 stopandgo 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” 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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(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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NOTICE
Do not drive the vehicle with the
warning light on—even for one block.
It may ruin the engine.
(h) “ABS” Warning Light
The light comes on when the ignition key
is turned to the “ON” position. If the anti
lock brake system and the brake assist
system works properly, the light turns off
after a few seconds. Thereafter, if the
system malfunctions, the light comes on
again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
antilock brake system, the brake assist
system, the traction control system and
vehicle skid control system do not oper-
ate, but the brake system still operates
conventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
antilock brake system does not operate
so that the wheels could lock up during
a sudden braking or braking on slippery
road surfaces. If either of the following conditions
occurs, this indicates a malfunction
somewhere in the parts monitored by
the warning light system. Contact your
Toyota dealer as soon as possible to
service the vehicle.The light does not come on when the
ignition key is turned to the “ON” posi-
tion, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
(i) Open Door Warning Light
This light remains on until all the doors
are completely closed.
(j) Open Power Sliding Door Warning Light and Buzzer
This light comes on if the power sliding
door is not completely closed with the
ignition key in the “ON” position.
If you forcibly close the power sliding door
by hand when the ignition key is in the
“ON” position, the open power sliding door
warning light may stay on. In this case,
try opening and closing the power sliding
door again by hand slowly, or use one of
the “DOOR L”, “DOOR R” or “PWR
DOOR” switch inside the vehicle or
“POWER DOOR”, “DPWR DOOR” or
“PPWR DOOR” switch of the wireless
remote control transmitter.
If you shift out of “P” when the power
sliding door is opened or in the process
of closing with the power sliding door sys-
tem on, a buzzer will sound and the open
power sliding door warning light will flash.
This is a warning that the sliding door is
not completely closed.

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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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“START”—Starter motor on. The key
will return to the “ON” position when
released.
For starting tips, see Section 3.
“ON”—Engine on and all accessories
on.
This is the normal driving position.
“ACC”—Accessories such as the radio
operate, but the engine is off.
If you leave the key in the “ACC” or
“LOCK” position and open the driver’s
door, a buzzer will remind you to remove
the key.
“LOCK”—Engine is off and the steering
wheel is locked. The key can be re-
moved only at this position.You must push in the key to turn the key
from “ACC” to the “LOCK” position. The
selector lever must be put in the “P” posi-
tion before pushing the key.
Vehicles with engine immobiliser system—
Once you remove the key, the engine im-
mobiliser system is automatically set. (See
“Engine immobiliser system” in Section
12.)
When starting the engine, the key may
seem stuck at the “LOCK” position. To
free it, first be sure the key is pushed all
the way in, and then rock the steering
wheel slightly while turning the key gently.
NOTICE
Do not leave the key in the “ON”
position if the engine is not running.
The battery will discharge and the
ignition could be damaged.
Ignition switch with steering
lock

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Your automatic transmission has a shift
lock system to minimize the possibility of
incorrect operation. This means you can
only shift out of “P” position when the
brake pedal is depressed (with the ignition
switch in “ON” or “ACC” position and the
selector lever pulled toward you).
(a) Selector lever
The shift position is displayed on the in-
strument cluster.
P:Parking, engine starting and
key removal
R: Reverse
N: Neutral
D: Normal driving (with overdrive on)
2: Stronger engine braking
L: Maximum engine braking
Automatic transmission
Selector lever Overdrive switch
With the brake pedal
depressed, shift while pulling
the selector lever toward you.
(The ignition switch must be
in “ON” or “ACC” position.)
Shift while pulling
the selector lever
toward you.
Shift normally.

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(b) Overdrive switch
You can select either third gear (with
overdrive off) or fourth gear (with over-
drive on) by pushing this switch.
To turn the overdrive off, push the switch.
The “O/D OFF” indicator light should come
on. To turn the overdrive on again, push
the switch again. The “O/D OFF” indicator
light should go off.
Always drive your vehicle with the over-
drive on for better fuel economy and
quieter driving.
If the engine is turned off when the over-
drive is off and restarted, the overdrive
will automatically be on.Vehicles with cruise control—When the
cruise control is being used, even if you
downshift the transmission by pushing and
releasing the overdrive switch, engine
braking will not be enabled because the
cruise control is not cancelled.
For ways to decrease the vehicle speed,
see “Cruise control” in this section.
(c) Normal driving
1. Start the engine as instructed in “How to start the engine” in Section 3. The
transmission must be in “P” or “N”.
2. With your foot holding down the brake pedal, shift the selector lever to “D”.
When the lever is in the “D” position, the
automatic transmission system will select
the most suitable gear for running condi-
tions such as normal cruising, hill climb-
ing, hard towing, etc.
Always turn the overdrive on for better
fuel economy and quieter driving. If the
engine coolant temperature is low, the
transmission will not shift into overdrive
gear even with the overdrive on.
CAUTION
Never put your foot on the accelera-
tor pedal while shifting.
3. Release the parking brake and brake pedal. Depress the accelerator pedal
slowly for smooth starting.
(d) Using engine braking
To use engine braking, you can downshift
the transmission as follows:
Push the overdrive switch. The “O/D
OFF” indicator light will come on and
the transmission will downshift to third
gear.
Shift into the “2” position. The trans-
mission will downshift to second gear
when the vehicle speed drops down to
or lower than 112 km/h (69 mph), and
stronger engine braking will be en-
abled.
Shift into the “L” position. The trans-
mission will downshift to first gear
when the vehicle speed drops down to
or lower than 58 km/h (36 mph), and
maximum engine braking will be en-
abled.
Vehicles with cruise control—When the
cruise control is being used, even if you
downshift the transmission by pushing and
releasing the overdrive switch, engine
braking will not be enabled because the
cruise control is not cancelled.