2003 TOYOTA TUNDRA check engine light

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Before making these checks, make sure
you have followed the correct starting pro-
cedure given in “How to start the engine”
in Section 3 and that you have sufficient
fuel.
If the engine is not turning over or is
turning over too slowly—
1. Check that the battery terminals are tight and clean.
2. If the battery terminals are O.K., switch on the interior light.
3. If the light is out, dim or goes out when the starter is cranked, the battery
is discharged. You may try jump start-
ing. See “(c) Jump starting” for further
instructions.
If the light is O.K., but the engine still will
not start, it needs adjustment or repair.
Call a Toyota dealer or qualified repair
shop.
NOTICE
Do not pull or pushstart the ve-
hicle. Your vehicle may suddenly
move when the engine starts, and
may damage itself or cause a colli-
sion. Also the threeway catalytic
converter may overheat and become a
fire hazard.
If the engine turns over at its normal
speed but will not start— 1. Turn the ignition key to “ACC” or “LOCK” and try starting the engine
again.
2. If the engine will not start, the engine may be flooded because of repeated
cranking. See “(b) Starting a flooded
engine” for further instructions.
3. If the engine still will not start, it needs adjustment or repair. Call a Toyota
dealer or qualified repair shop. If the engine will not start, your engine
may be flooded because of repeated
cranking.
If this happens, turn the key to “START”
with the accelerator pedal fully depressed.
Keep the key and accelerator pedal in
these positions for 15 seconds and re-
lease them. Then try starting the engine
with your foot off the accelerator pedal.
If the engine does not start after 15 se-
conds of cranking, release the key, wait
a few minutes and try again.
If the engine still will not start, it needs
adjustment or repair. Call a Toyota dealer
or qualified repair shop for assistance.
NOTICE
Do not crank for more than 30 se-
conds at a time. This may overheat
the starter and wiring systems.
If your vehicle will not start—
(a) Simple checks
(b) Starting a flooded engine
(5VZFE engine)

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Connecting point for 5VZFE engine
Connecting point for 2UZFE engine
Do not connect the cable to or near
any part that moves when the engine
is cranked.
CAUTION
When making the connections, to
avoid serious injury, do not lean over
the battery or accidentally let the
jumper cables or clamps touch any-
thing except the correct battery termi-
nals or the ground.
5. Start your engine in the normal way.
After starting, run it at about 2000 rpm
for several minutes with the accelerator
pedal lightly depressed.
6. Carefully disconnect the cables in the exact reverse order: the negative cable
and then the positive cable.
7. Carefully dispose of the battery cover cloths—they may now contain sulfuric
acid.
8. If removed, replace all the battery vent plugs.
If the cause of your battery discharging is
not apparent (for example, lights left on),
you should have it checked at your Toyota
dealer. If your engine stalls while driving...
1. Reduce your speed gradually, keeping a straight line. Move cautiously off the
road to a safe place.
2. Turn on your emergency flashers.
3. Turn the ignition key to “ACC” or “LOCK”, and try starting the engine
again.
If the engine will not start, see “If your
vehicle will not start”.
CAUTION
If the engine is not running, the pow-
er assist for the brakes and steering
will not work, so steering and braking
will be much harder than usual.
If your engine stalls while
driving

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3. Visually check to see if the engine
drive belt (fan belt) is broken or loose.
Look for obvious coolant leaks from the
radiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the engine drive belt is broken or thecoolant is leaking, stop the engine im-
mediately. Call a Toyota dealer for as-
sistance.
5. If the engine drive belt is O.K. and there are no obvious leaks, you may
help the engine cool down more quickly
by running it at about 1500 rpm for a
few minutes with the accelerator pedal
lightly depressed.
6. Check the coolant reservoir. If it is dry, add coolant to the reservoir while the
engine is running. Fill it about half full.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
7. After the engine coolant temperaturehas cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You s hould have it checked as
soon as possible at your Toyota dealer.
1. Reduce your speed gradually, keeping a straight line. Move cau-
tiously off the road to a safe place
well away from the traffic. Avoid
stopping on the center divider of
a highway. Park on a level spot
with firm ground.
2. Stop the engine and turn on your emergency flashers.
3. Firmly set the parking brake and put the transmission in “P” (auto-
matic) or reverse (manual).
4. Have everyone get out of the ve- hicle on the side away from traffic.
5. Read the following instructions thoroughly.
If you have a flat tire—

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Power steering fluid level (2UZFE en-
gine)
Check the level through the reservoir. The
level should be in the “HOT” or “COLD”
range depending on the fluid temperature.
See Section 7−2 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.)
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 seat controls such as seat
adjusters, seatback recliner, etc. operate
smoothly and that all latches lock securely
in any position. Check that the head re-
straints move up and down smoothly and
that the locks hold securely in any latched
position. For folding
−down seatback
(bench seat), 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 the belt
webbing is not cut, frayed, worn or dam-
aged.
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 (pedal type)
Check that the pedal has the proper travel
and that, on a safe incline, your vehicle
is held securely with only the parking
brake applied.
Parking brake (lever type)
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
On a safe incline, check that your vehicle
is held securely with the selector lever in
“P” position and all brakes released.
OUTSIDE THE VEHICLE
Items listed below should be performed
from time to time, unless otherwise
specified.
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.

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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 ground. After turn-
ing 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 filler cap hand −tight.
Oil quantity, L (qt., lmp. qt.): 5VZ− FE engine 1.2 (1.3, 1.1)
2UZ− FE engine 1.5 (1.6, 1.3)
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.
Checking the engine oil level

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If any of the above parts are extremely
dirty or you are not sure of their condi-
tion, take your vehicle to a Toyota dealer.
CAUTION
To prevent burning yourself, be care-
ful not to touch the radiator or con-
denser when the engine is hot.
NOTICE
To prevent damage to the radiator
and condenser, do not perform the
work by yourself.
To check the fluid level, simply look at
the seethrough reservoir. The level
should be between the “MAX” and
“MIN” lines on the reservoir.
It is normal for the brake fluid level to go
down slightly as the brake pads wear. So
be sure to keep the reservoir filled.
If the reservoir needs frequent refi lling, it
may indicate a serious mechanical prob-
lem. If the level is low, add SAE J1703 or
FMVSS No.116 DOT 3 brake fluid to the
brake reservoir.
Remove and replace the reservoir cap by
hand. Fill the brake fluid to the dotted
line. This brings the fluid to the correct
level when you put the cap back on.
Use only newly opened brake fluid. Once
opened, brake fluid absorbs moisture from
the air, and excess moisture can cause a
dangerous loss of braking.
CAUTION
Take care when filling the r
eservoir
because brake fluid can harm your
eyes and damage painted surfaces. If
fluid gets in your eyes, flush your
eyes with clean water immediately. If
you still feel uncomfortable with your
eyes, go to the doctor.
NOTICE
If you spill the fluid, be sure to wash
it off with water to prevent it from
damaging the parts or paint.
Checking the radiator and
condenser Checking brake fluid

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NOTICE
Be sure the engine and all accesso-
ries are off before performing main-
tenance.
 When checking the battery, remove
the ground cable from the negative
terminal (“” mark) first and rein-
stall it last.
 Be careful not to cause a short cir-
cuit with tools.
 Take care no solution gets into the
battery when washing it.
Ty p e A
Green Dark Clear or
light yellow
Ty p e B Blue White Red
CHECKING BY INDICATOR
Check the battery condition by the indi-
cator color.
Indicator color
ConditionTy p e ATy p e B
GreenBlueGood
DarkWhite
"\b \b #


 $%

&\f 

 '


\f
Clear or Light
Yellow
Red
Have battery
checked by your
Toyota dealer.
—Checking battery c ondition

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During recharging, the battery is pro-
ducing hydrogen gas.
Therefore, before recharging:
1. If recharging with the battery installed on the vehicle, be sure to disconnect
the ground cable.
2. Be sure the power switch on the re- charger is off when connecting the
charger cables to the battery and when
disconnecting them.
CAUTION
Always charge the battery in an un-
confined area. Do not charge the
battery in a garage or closed room
where there is not sufficient ventila-
tion.
Only do a slow charge (5 A or
less). Charging at a quicker rate is
dangerous. The battery may ex-
plode, causing personal injuries.
NOTICE
Never recharge the battery while the
engine is running. Also, be sure all
accessories are turned off.
Ty p e A
Good Blown
Ty p e B
Ty p e C Good Blown
Good Blown
If the headlights or other electrical
components do not work, check the
fuses. If any of the fuses are blown,
they must be replaced.
See “Fuse locations” in Section 7
−1 for
locations of the fuses.
Turn the ignition switch and inoperative
component off. Pull a suspected fuse
straight out and check it.
Determine which fuse may be causing the
problem. The lid of the fuse box shows
the name of the circuit for each fuse. See
Section 8 of this manual for the functions
controlled by each circuit.
Battery recharging precautions Checking and replacing fuses