2003 TOYOTA SIENNA Owners Manual

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Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See Section 72 for addi-
tional information.
Power steering fluid level
Check the level through the reservoir. The
level should be in the “HOT” or “COLD”
range depending on the fluid temperature.
See Section 72 for additional information.
Exhaust system
If you notice any change in the sound of
the exhaust or smell exhaust fumes, have
the cause located and corrected immedi-
ately. (See “Engine exhaust cautions” in
Section 2.)Be on the alert for changes in perfor-
mance, sounds, and visual tipoffs that
indicate service is needed. Some impor-
tant clues are as follows:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A leak under the vehicle (however, wa-
ter dripping from the air conditioning
after use is normal.)
Change in exhaust sound (This may
indicate a dangerous carbon monoxide
leak. Drive with the windows open and
have the exhaust system checked im-
mediately.)
Flatlooking tire; excessive tire squeal
when cornering; uneven tire wear
Vehicle pulls to one side when driving
straight on a level road
Strange noises related to suspension
movement
Loss of brake effectiveness; spongy
feeling brake pedal; pedal almost
touches floor; vehicle pulls to one side
when braking
Engine coolant temperature continually
higher than normalIf you notice any of these clues, take your
vehicle to your Toyota dealer as soon as
possible. It probably needs adjustment or
repair.
CAUTION
Do not continue driving with the ve-
hicle unchecked. It could result in se-
rious vehicle damage and possibly
personal injury.
Does your vehicle need
repairing?

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Some states have vehicle emission in-
spection programs which include OBD
(OnBoard Diagnostics) checks.
The OBD system monitors the operation
of the emission control system. When the
OBD system determines that a problem
exists somewhere in the emission control
system, the malfunction indicator lamp
comes on. In this case, your vehicle may
not pass the I/M test and need to be
repaired. Contact your Toyota dealer to
service the vehicle.
Even if the malfunction indicator lamp
does not come on, your vehicle may not
pass the I/M test as readiness codes
have not been set in the OBD system.
Readiness codes are automatically set
during ordinary driving. However, when the
battery is disconnected or run down, the
codes are erased. Also, depending on
your driving habits, the codes may not be
completely set.
Also, if the malfunction indicator lamp had
come on recently due to temporary mal-
function such as a loose fuel tank cap,
your vehicle may not pass the I/M test. The malfunction indicator lamp will go off
after taking several driving trips, but the
error code in the OBD system will not be
cleared unless about 40 trips or more are
taken.
If your vehicle does not pass the I/M test
even the malfunction indicator lamp does
not come on, contact your Toyota dealer
to prepare the vehicle for retesting.
Emissions Inspection and
Maintenance (I/M) programs

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DOITYOURSELF MAINTENANCE
Introduction
Engine compartment overview288
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Fuse locations 289
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Doityourself service precautions 290
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Positioning the jack 291
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Parts and tools 292
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SECTION 7 1

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1. Engine coolant reservoir
2. Power steering fluid reservoir
3. Engine oil level dipstick
4. Engine oil filler cap
5. Brake fluid reservoir
6. Fuse blocks
7. Battery
8. Radiator
9. Electric cooling fans
10. Condenser
11. Windshield and rear window washer fluid tank
Engine compartment overview

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Spare fuses
Fuse locations

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If you perform maintenance by yourself,
be sure to follow the correct procedure
given in this section.
You should be aware that improper or in-
complete servicing may result in operating
problems.
Performing doityourself maintenance
during the warranty period may affect your
warranty coverage. Read the separate
Toyota Warranty statement for details and
suggestions.
This section gives instructions only for
those items that are relatively easy for an
owner to perform. As explained in Section
6, there are still a number of items that
must be done by a qualified technician
with special tools.
For information on tools and Sections for
doityourself maintenance, see “Parts
and tools”.
Utmost care should be taken when work-
ing on your vehicle to prevent accidental
injury. Here are a few precautions that
you should be especially careful to ob-
serve:CAUTION
When the engine is running, keep
hands, clothing, and tools away
from the moving fan and engine
drive belts. (Removing rings,
watches, and ties is advisable.)
Right after driving, the engine
compartment—the engine, radiator,
exhaust manifold and spark plug
boots, etc.—will be hot. So be care-
ful not to touch them. Oil, fluids
and spark plugs may also be hot.
If the engine is hot, do not remove
the radiator cap or loosen the drain
plugs to prevent burning yourself.
Do not smoke, cause sparks or al-
low open flames around fuel or the
battery. Their fumes are flammable.
Do not get under your vehicle with
just the body jack supporting it. Al-
ways use automotive jack stands or
other solid supports.
Be sure that the ignition is off if
you work near the electric cooling
fans or radiator grille. With the
ignition on, the electric cooling fans
will automatically start to run if the
engine coolant temperature is high
and/or the air conditioning is on.
Use eye protection whenever you
work on or under your vehicle
where you may be exposed to flying
or falling material, fluid spray, etc.
Used engine oil contains potentially
harmful contaminants which may
cause skin disorders such as in-
flammation or skin cancer, so care
should be taken to avoid prolonged
and repeated contact with it. To re-
move used engine oil from your
skin, wash thoroughly with soap
and water.
Do not leave used oil within the
reach of children.
Dispose of used oil and filter only
in a safe and acceptable manner.
Do not dispose of used oil and fil-
ter in household trash, in sewers or
onto the ground. Call your dealer or
a service station for information
concerning recycling or disposal.
Doityourself service
precautions

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Be extremely cautious when work-
ing on the battery. It contains poi-
sonous and corrosive sulfuric acid.
Warning: Battery posts, terminals
and related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
NOTICE
Remember that battery and ignition
cables carry high currents or volt-
ages. Be careful of accidentally
causing a short circuit.
 Add only demineralized or distilled
water to fill the radiator. And if you
spill some of the coolant, be sure
to wash off with water to prevent it
from damaging the parts or paint.
 Do not allow dirt or anything else
to fall through the spark plug holes.
 Do not pry the outer electrode of a
spark plug against the center elec-
trode.
Use only spark plugs of the speci-
fied type. Using other types will
cause engine damage, loss of per-
formance or radio noise.
 Do not reuse iridiumtipped spark
plugs by cleaning or regapping.
 Do not overfill automatic transmis-
sion fluid and power steering fluid,
or the transmission and power
steering could be damaged.
 Do not drive with the air cleaner
filter removed, or excessive engine
wear could result. Also backfiring
could cause a fire in the engine
compartment.
 Be careful not to scratch the glass
surface with the wiper frame.
 When closing the engine hood,
check to see that you have not for-
gotten any tools, rags, etc.Front
Do not jack up
Positioning the jack

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When jacking up your vehicle with the
jack, position the jack correctly as
shown in the illustrations.
CAUTION
When jacking, be sure to observe the
following to reduce the possibility of
personal injury:
Follow jacking instructions.
Do not put any part of your body
under the vehicle supported by the
jack. Personal injury may occur.
Do not start or run the engine while
your vehicle is supported by the
jack.
Stop the vehicle on a level firm
ground, firmly set the parking brake
and put the transmission in “P”.
Block the wheels on the opposite
side of the jack up point if neces-
sary.
Make sure to set the jack properly
in the jack point. Raising the ve-
hicle with jack improperly posi-
tioned will damage the vehicle or
may allow the vehicle to fall off the
jack and cause personal injury.
Never get under the vehicle when
the vehicle is supported by the jack
alone; use vehicle support stands.
Do not raise the vehicle with some-
one in the vehicle.
When raising the vehicle, do not
put an object on or under the jack.
NOTICE
Make sure to place the jack correctly,
or your vehicle may be damaged.
Here is a list of parts and tools you will
need on performing doityourself mainte-
nance. Remember all Toyota parts are de-
signed in metric sizes, so your tools must
be metric.
CHECKING THE ENGINE OIL LEVEL
Parts (if level is low):
“Toyota Genuine Motor Oil” or equiva-
lent
See Section 72 for details about en-
gine oil selection.
Tools:
Rag or paper towel
Funnel (only for adding oil)
CHECKING THE ENGINE COOLANT
LEVEL
Parts (if level is low):
“Toyota Genuine Long Life Coolant” or
equivalent
See Section 72 for details about cool-
ant type selection.
Demineralized or distilled water
Tools:
Funnel (only for adding coolant)
Parts and tools