2003 TOYOTA COROLLA check engine

’03 Corolla U (L/O 0201)
1972003 MY COROLLA_U (OM12744U)
If you are a skilled doityourself mechan-
ic, the Toyota service manuals are recom-
mended. Please be aware that doityour-
self maintenance can affect your warranty
coverage. See “Owner ’s Warranty Informa-
tion Booklet” or “Owner ’s Manual Supple-
ment” for the details.Listed below are the general maintenance
items that should be performed as fre-
quently as specified. In addition to check-
ing the items listed, if you notice any
unusual noise, smell or vibration, you
should investigate the cause or take your
vehicle to your Toyota dealer or a quali-
fied service shop immediately. It is recom-
mended that any problem you notice be
brought to the attention of your dealer or
the qualified service shop for their advice.
CAUTION
Make these checks only where ade-
quate ventilation can be obtained if
you run the engine.
OUTSIDE THE VEHICLE
Items listed below should be performed
from time to time, unless otherwise
specified.
Tire pressure
Check the pressure with a gauge every
two weeks, or at least once a month. See
page 214 in Section 72 for additional
information.Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See page 215 in Sec-
tion 72 for additional information. When
checking the tires, make sure no nuts are
missing, and check the nuts for loose-
ness. Tighten them if necessary.
Tire rotation
Rotate the tires according to the mainte-
nance schedule. (For scheduled mainte-
nance information, please refer to the
“Scheduled Maintenance Guide” or “Own-
er ’s Manual Supplement”.) See page 216
in Section 72 for additional information.
Fluid leaks
Check underneath for leaking fuel, oil, wa-
ter or other fluid after the vehicle has
been parked for a while. If you smell fuel
fumes or notice any leak, have the cause
found and corrected immediately.
Doors and engine hood
Check that all doors including trunk lid
operate smoothly and all latches lock se-
curely. Make sure the engine hood sec-
ondary latch secures the hood from open-
ing when the primary latch is released.
General maintenance

’03 Corolla U (L/O 0201)
1982003 MY COROLLA_U (OM12744U)
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.
Lights
Make sure the headlights, stop lights, tail
lights, turn signal lights, and other lights
are all working. Check headlight aim.
Service reminder indicators and warning
buzzers
Check that all service reminder indicators
and warning buzzers function properly.
Steering wheel
Be alert for changes in steering condition,
such as hard steering or strange noise.
Seats
Check that all front seat controls such as
seat adjusters, seatback recliner, etc. op-
erate smoothly and that all latches lock
securely in any position. Check that the
head restraints move up and down
smoothly and that the locks hold securely
in any latched position. For foldingdown
rear seatbacks, check that the latches
lock securely.Seat belts
Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly. Make sure that the
belt webbings are not cut, frayed, worn or
damaged.
Accelerator pedal
Check the pedal for smooth operation and
uneven pedal effort or catching.
Clutch pedal
Check the pedal for smooth operation.
Brake pedal
Check the pedal for smooth operation and
that the pedal has the proper clearance.
Check the brake booster function.
Brakes
At a safe place, check that the brakes do
not pull to one side when applied.
Parking brake
Check that the lever has the proper travel
and that, on a safe incline, your vehicle
is held securely with only the parking
brake applied.
Automatic transmission “Park” mecha-
nism
Check the lock release button of the se-
lector lever for proper and smooth opera-
tion. On a safe incline, check that your
vehicle is held securely with the selector
lever in “P” position and all brakes re-
leased.
IN THE ENGINE COMPARTMENT
Items listed below should be checked
from time to time, e.g. each time when
refueling.
Washer fluid
Make sure there is sufficient fluid in the
tank. See page 225 in Section 73 for
additional information.
Engine coolant level
Make sure the coolant level is between
the “FULL” and “LOW” lines on the see
through reservoir when the engine is cold.
See page 211 in Section 72 for additional
information.
Radiator, condenser and hoses
Check that the front of the radiator and
condenser are clean and not blocked with
leaves, dirt, or insects. See page 212 in
Section 72 for additional information.

’03 Corolla U (L/O 0201)
1992003 MY COROLLA_U (OM12744U)
Battery condition
Check the battery condition by the indica-
tor color. See page 222 in Section 73 for
additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See page 213 in Section 72 for addition-
al information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See page 210 in Section
72 for additional 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 page 213 in Section 72 for addition-
al 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” on
page 147 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 or clutch pedal; pedal al-
most 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?

’03 Corolla U (L/O 0201)
2052003 MY COROLLA_U (OM12744U)
Do not reuse iridiumtipped spark
plugs by cleaning or regapping.
 Do not overfill automatic transmis-
sion fluid, or the transmission
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
Rear
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”
(automatic) or reverse (manual).
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.
Positioning the jack

’03 Corolla U (L/O 0201)
2062003 MY COROLLA_U (OM12744U)
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
place any objects on top of or un-
derneath 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):
Engine oil API grade SL
“EnergyConserving” or ILSAC
multigrade having viscosity proper for
your climate
Tools:
Rag or paper towel
Funnel (only for adding oil)
CHECKING THE ENGINE COOLANT
LEVEL
Parts (if level is low):
“TOYOTA Long Life Coolant” or equiva-
lent
See page 211 in Section 72 for details
about coolant type selection.
Demineralized or distilled water
Tools:
Funnel (only for adding coolant) CHECKING BRAKE FLUID
Parts (if level is low):
SAE J1703 or FMVSS No.116 DOT 3
brake fluid
Tools:
Rag or paper towel
Funnel (only for adding fluid)
CHECKING POWER STEERING FLUID
Parts (if level is low):
Automatic transmission fluid
DEXRON II or III
Tools:
Rag or paper towel
Funnel (only for adding fluid)
CHECKING BATTERY CONDITION
Tools:
Warm water
Baking soda
Grease
Conventional wrench (for terminal
clamp bolts)
CHECKING AND REPLACING FUSES
Parts (if replacement is necessary):
Fuse with same amperage rating as
original
Parts and tools

’03 Corolla U (L/O 0201)
2092003 MY COROLLA_U (OM12744U)
DOITYOURSELF MAINTENANCE
Engine and Chassis
Checking the engine oil level210
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Checking the engine coolant level 211
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Checking the radiator and condenser r212
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Checking brake fluid 213
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Checking power steering fluid 213
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Checking tire pressure 214
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Checking and replacing tires 215
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Rotating tires 216
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Installing snow tires and chains 217
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Replacing wheels 218
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Aluminum wheel precautions 219
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SECTION 7 2

’03 Corolla U (L/O 0201)
2102003 MY COROLLA_U (OM12744U)
Low level Full level
Add oil O.K. Too full
With the engine at operating tempera-
ture and turned off, check the oil level
on the dipstick. 1. To get a true reading, the vehicle should be on a level spot. After turning
off the engine, wait a few minutes for
the oil to drain back into the bottom of
the engine.
2. Pull the dipstick out, hold a rag under the end and wipe it clean.
3. Reinsert the dipstick—push it in as far as it will go, or the reading will not be
correct.
4. Pull the dipstick out and look at the oil level while holding a rag under the
end.
NOTICE
Be careful not to drop the engine oil
on the vehicle components.
If the oil level is below or only slightly
above the low level, add engine oil of
the same type as already in the engine.
Remove the oil filler cap and add engine
oil in small quantities at a time, checking
the dipstick. We recommend that you use
a funnel when adding oil.
The approximate quantity of oil needed to
fill between the low level and the full level
on the dipstick is indicated below for ref-
erence.
When the level reaches within the correct
range, install the f iller cap handtight.
Oil quantity, L (qt., lmp. qt.): 1.3 (1.4, 1.1)
NOTICE
 Be careful not to spill the engine
oil on the vehicle components.
 Avoid overfilling, or the engine
could be damaged.
 Check the oil level on the dipstick
once again after adding the oil.
ENGINE OIL SELECTION
Use API grade SL “EnergyConserving” or
ILSAC multigrade engine oil.
Recommended viscosity:
SAE 5W30
Outside temperature
SAE 5W30 is the best choice for good
fuel economy, and good starting in cold
weather.
If SAE 5W30 oil is not available, SAE
10W30 oil may be used. However, it
should be replaced with SAE 5W30 at
the next oil change.
Checking the engine oil level

’03 Corolla U (L/O 0201)
2112003 MY COROLLA_U (OM12744U)
API service symbol
ILSAC certification mark
Oil identification marks
Either or both API registered marks are
added to some oil containers to help
you select the oil you should use.
The API Service Symbol is located any-
where on the outside of the container.
The top portion of the label shows the oil
quality by API (American Petroleum Insti-
tute) designations such as SL. The center
portion of the label shows the SAE viscos-
ity grade such as SAE 5W30. “Energy
Conserving” shown in the lower portion,
indicates that the oil has fuelsaving ca-
pabilities.
The ILSAC (International Lubricant Stan-
dardization and Approval Committee) Certi-
fication Mark is displayed on the front of
the container.Look at the seethrough coolant reser-
voir when the engine is cold. The cool-
ant level is satisfactory if it is between
the “FULL” and “LOW” lines on the
reservoir. If the level is low, add ethyl-
eneglycol type coolant for a proper
corrosion protection of aluminum com-
ponents.
The coolant level in the reservoir will vary
with engine temperature. However, if the
level is on or below the “LOW” line, add
coolant. Bring the level up to the “FULL”
line.
Always use ethyleneglycol type coolant
for a proper corrosion protection of alumi-
num components. See information in the
next column.
If the coolant level drops within a short
time after replenishing, there may be a
leak in the system. Visually check the
radiator, hoses, engine coolant filler cap,
radiator cap and drain cock and water
pump.
If you can find no leak, have your Toyota
dealer test the cap pressure and check
for leaks in the cooling system.
Checking the engine coolant
level