check engine TOYOTA TUNDRA 2003 1.G Owners Manual

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Model code
Check the model code to see what type of model your vehicle is.
V C K 3 0 T R D
The model code appears on the manufacturer ’s plate with the heading “MODEL”.
See “Your Toyota’s identification” in Section 2 for the Certification Label location.
Grade
D: Standard grade
S: SR5 grade
L: Limited grade
Engine type
VCK: 5VZ −FE engine
UCK: 2UZ −FE engine
Driving system
30: Two− wheel drive
40: Four −wheel driveDeck type
R: Standard bed
S: StepSide bed
Cap type
T: Standard cab
A: Access cab

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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 stop−and− go 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.
IdlingNormal
driving
The oil pressure gauge indicates engine
oil pressure when the ignition switch is
on. Check it while driving to make sure
that the needle is in the proper range.
If the oil pressure should stay below the
normal range, pull off the road to a safe
place and stop the engine immediately.
Call a Toyota dealer or qualified repair
shop for assistance.
Oil pressure may not build up when the
oil level is too low. The oil pressure
gauge is not designed to indicate oil level,
and the oil level must be checked using
the level dipstick.
Oil pressure gauge

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NOTICE
Do not drive the vehicle with the oil
pressure below the normal range until
the cause is fixed—it may ruin the
engine.
The voltmeter tells whether the battery
is charged or discharged. Check it
while the engine is running—the needle
should always indicate as shown above.
If the needle reads below or above the
normal range while the engine is running,
it indicates the charging system needs im-
mediate repair.
However, it is normal for the needle to
drop below the normal range during en-
gine starting.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.
Voltmeter 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...
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.
CAUTION
If the light does not turn off even
after the parking brake is released
while the engine is running, immedi-
ately stop your vehicle at a safe
place and contact your Toyota dealer.
In this case, the brakes may not work
properly and your stopping distance
will become longer. Depress the brake
pedal firmly and bring the vehicle to
an immediate stop.
(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” or
“START”, the reminder light flashes and
buzzer sounds if the driver ’s seat belt is
not fastened. 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” or
“START”, the reminder light flashes if a
passenger sits in the front passenger seat
and does not fasten the seat belt. Howev-
er, if a front passenger uses an additional
seat cushion, the light may not flash even
when the seat belt is not buckled up.
If luggage or other load is placed on the
front passenger seat, depending on its
weight and how it is placed on the seat,
built −in sensors in the seat cushion may
detect the pressure, causing the reminder
light to keep flashing.
(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.

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NOTICE
Do not continue driving if the engine
drive belt is broken or loose.
(e) 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.
NOTICE
Do not drive the vehicle with the
warning light on—even for one block.
It may ruin the engine.
(f) 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, elec-
tronic throttle control system, automatic
transmission electrical system or warn-
ing light system itself.
Contact your Toyota dealer as soon as
possible to service the vehicle.
5VZ− FE engine—
If the engine speed does not increase with
the accelerator pedal depressed down to
about the middle position, there may be
a problem somewhere in your electronic
throttle control system.
At this time, if you depress the accelera-
tor pedal more firmly and slowly, you can
drive your vehicle at low speeds. Have
your vehicle checked by your Toyota deal-
er as soon as possible.
Even if the abnormality of the electronic
throttle control system is corrected during
low speed driving, the system may not be
recovered until the engine is stopped and
the ignition key is turned to “ACC” or
“LOCK” position.

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CAUTION
Be especially careful to prevent erro-
neous pedal operation.
2UZ−FE engine—
If the engine speed does not increase with
the accelerator pedal depressed down,
there may be a problem somewhere in
your electronic throttle control system.
At this time, vibration may occur. Howev-
er, if you depress the accelerator pedal
more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle
checked by your Toyota dealer as soon as
possible.
Even if the abnormality of the electronic
throttle control system is corrected during
low speed driving, the system may not be
recovered until the engine is stopped and
the ignition key is turned to “ACC” or
“LOCK” position.
CAUTION
Be especially careful to prevent erro-
neous pedal operation.
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
(On −Board Diagnostics) system before
taking your vehicle for the inspection.
For details, see “Emissions Inspection and
Maintenance (I/M) programs” in Section 6.
(g) 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. (h) “ABS” Warning Light
The light comes on when the ignition key
is turned to the “ON” position. If the anti
−
lock brake system works properly, the
light turns off after a few seconds. There-
after, 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
anti −lock brake system does not operate,
but the brake system still operates con-
ventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock 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 oc-
curs, this indicates a malfunction some-
where in the components 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 the light remains on.
The light comes on while you are driv-
ing.

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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 and
SRS warning light should come on. The
“ABS” warning light goes off after a
few seconds.
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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If the preset speed automatically cancels
out other than for the above cases, have
your vehicle checked by your Toyota deal-
er at the earliest opportunity.
RESETTING TO A FASTER SPEED
Push the lever up in the “+ RES” direction
and hold it. Release the lever when the
desired speed is attained. While the lever
is held up, the vehicle will gradually gain
speed.
However, a faster way to reset is to ac-
celerate the vehicle and then push the
lever down in the “− SET” direction.
RESETTING TO A SLOWER SPEED
Push the lever down in the “− SET” direc-
tion and hold it. Release the lever when
the desired speed is attained. While the
lever is held down, the vehicle speed will
gradually decrease.
However, a faster way to reset is to de-
press the brake pedal and then push the
lever down in the “− SET” direction. On vehicles with automatic transmission,
even if you turn off the overdrive switch
with the cruise control on, engine braking
will not be applied because the cruise
control is not cancelled. To decrease the
vehicle speed, reset to a slower speed
with the cruise control lever or depress
the brake pedal. If you use the brake
pedal, cruise control is cancelled.
RESUMING THE PRESET SPEED
If the preset speed is cancelled by pulling
the control lever or by depressing the
brake pedal or clutch pedal, pushing the
lever up in the “+ RES” direction will re-
store the speed set prior to cancellation.
However, once the vehicle speed falls be-
low about 40 km/h (25 mph), the preset
speed will not be resumed.
CRUISE CONTROL FAILURE WARNING
If the “CRUISE” indicator light in the
instrument cluster flashes when using the
cruise control, press the “ON
−OFF” button
to turn the system off and then press it
again to turn it on.
If any of the following conditions then oc-
curs, there is some trouble in the cruise
control system.
The indicator light does not come on.
The indicator light flashes again.
The indicator light goes out after it
comes on.
If this is the case, contact your Toyota
dealer and have your vehicle inspected.

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Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel systems 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”.CAUTION
Avoid inhaling the engine exhaust.
It contains carbon monoxide, which
is a colorless and odorless gas. It
can cause unconsciousness or even
death.
Make sure the exhaust system has
no holes or loose connections. The
system should be checked from
time to time. If you hit something,
or notice a change in the sound of
the exhaust, have the system
checked immediately.
Do not run the engine in a garage
or enclosed area except for the
time needed to drive the vehicle in
or out. The exhaust gases cannot
escape, making this a particularly
dangerous situation.
Do not remain for a long time in a
parked vehicle with the engine run-
ning. If it is unavoidable, however,
do so only in an unconfined area
and adjust the heating or cooling
system to force outside air into the
vehicle.
To allow proper operation of your
vehicle’s ventilation system, keep
the inlet grilles in front of the wind-
shield clear of snow, leaves, or oth-
er obstructions.
If you smell exhaust fumes in the
vehicle, drive with the windows
open. Have the cause immediately
located and corrected.
Toyota does not recommend occu-
pying the rear cargo area when it
is fitted with a slidein camper,
camper shell or other type cover
while the engine is running. This
caution applies to both driving and
stopped or parked situations with
the engine running. Particular care
should be taken to prevent exhaust
gases from entering camper bodies,
trailers or other enclosures on or
around your vehicle. If exhaust
fumes are detected, open all win-
dows and thoroughly ventilate the
area.
Engine exhaust cautions

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FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining the engine in proper working order.
ENGINE OIL CONSUMPTION
It is normal that an engine should con-
sume some engine oil during normal
engine operation. The causes of oil
consumption in a normal engine are as
follows.
Oil is used to lubricate pistons, piston
rings and cylinders. A thin film of oil
is left on the cylinder wall when a pis-
ton moves downwards in the cylinder.
High negative pressure generated when
the vehicle is decelerating sucks some
of this oil into the combustion chamber.
This oil as well as some part of the oil
film left on the cylinder wall is burned
by the high temperature combustion
gases during the combustion process.
Oil is also used to lubricate the stems
of the intake valves. Some of this oil
is sucked into the combustion chamber
together with the intake air and is
burned along with the fuel. High tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems. The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by high
−speed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 lmp. qt./600
miles)
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately.
As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an expressway, making it
appear that oil is excessively consumed
after driving at high speeds. IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
For detailed information on oil level check,
see “Checking the engine oil level” in Sec-
tion 7
−2.
Facts about engine oil
consumption