2003 TOYOTA TUNDRA wiring

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
When the front seat belt pretensioners are
activated, an operating noise may be
heard and a small amount of smoke −like
gas may be released. This gas is harm-
less and does not indicate that a fire is
occurring.
Once the front seat belt pretensioners
have been activated, the seat belt retrac-
tors remain locked.
CAUTION
Do not modify, remove, strike or open
the front seat belt pretensioner as-
semblies, airbag sensor or surround-
ing area or wiring. Doing so may
cause sudden operation of the front
seat belt pretensioners or disable the
system, which could result in death
or serious injury.
Failure to follow these instructions
can result in death or serious inju-
ries. Consult your Toyota dealer
about any repairs and modifications.
NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can
interfere with proper operation of the
front seat belt pretensioners in some
cases.
 Installation of electronic devices
such as a mobile twoway radio,
cassette tape player or compact
disc player
 Repairs on or near the front seat
belt pretensioner assemblies
 Modification of the suspension sys-
tem
 Modification of the front end struc-
ture
 Attachment of a grille guard (bull
bar, kangaroo bar, etc.), snowplow,
winches or any other equipment to
the front end
 Repairs made on or near the front
fenders, front end structure or con-
sole
This front seat belt pretensioner system
has a service reminder indicator to inform
the driver of operating problems. If any of
the following conditions occurs, this
indicates a malfunction of the airbags or
pretensioners. 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 or flashes while
driving.
If either front seat belt does not retract
or cannot be pulled out due to a mal-
function or activation of the relevant
front seat belt pretensioner.

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This indicator comes on when the igni-
tion key is turned to the “ON” position.
It goes off after about 6 seconds. This
means the SRS airbags are operating
properly.
This warning light system monitors the
airbag sensor assembly, front airbag sen-
sors, inflators, warning light, interconnect-
ing wiring and power sources. (For details,
see “Service reminder indicators and
warning buzzers” in Section 1− 5.)
TABLE 1: A PASSENGER RISK GROUP
Infant. An infant (less than 1 year old) who must ride in the front seat because:
Vehicle has no rear seat;
Vehicle has a rear seat too small to accommodate a rear −facing infant seat;
or
The infant has a medical condition which, according to the infant’s physician,
makes it necessary for the infant to ride in the front seat so that the driver
can constantly monitor the child’s condition.
Child age 1 to 12. A child age 1 to 12 must ride in the front seat because:
Vehicle has no rear seat:
Although children ages 1 to 12 ride in the rear seat(s) whenever possible,
children ages 1 to 12 sometimes must ride in the front because no space is
available in the rear seat(s) of vehicle; or
The child has a medical condition which, according to the child’s physician,
makes it necessary for the child to ride in the front seat so that the driver can
constantly monitor the child’s condition.
Medical condition. A passenger has a medical condition which according to his
or her physician:
Causes the passenger airbag to pose a special risk for the passenger: and
Makes the potential harm from the passenger airbag in a crash greater than the
potential harm from turning off the airbag and allowing the passenger, even if
belted, to hit the dashboard, or windshield in a crash.
For more detailed information concerning about the passenger risk group, please
contact NHTSA at 1 −800− 424−9393 or Transport Canada at 1 −800− 333−0371.

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A warning light turning on briefly during
operation does not indicate a problem.
(i) Open Door Warning Light
This light remains on until all the doors
are completely closed.
(j) SRS Warning Light
This light will come on when the igni-
tion key is turned to the “ON” position.
After about 6 seconds, the light will go
off. This means the system of the air-
bag and front seat belt pretensioners
are operating properly.
The warning light system monitors the air-
bag sensor assembly, front airbag sen-
sors, front seat belt pretensioner assem-
blies, inflators, warning light,
interconnecting wiring and power sources.
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 the light remains on.
The light comes on or flashes while
driving. (k) Unengaged “Park” Warning Light
(with automatic transmission and
front drive control lever)
This light warns that the transmission
“Park” mechanism is not engaged. If the
front drive control lever is in the “N” posi-
tion while the selector lever is in the “P”
position, the transmission will disengage
and the wheels will not lock.
CAUTION
To restore the park function, shift the
front drive control lever out of “N”,
or the vehicle can move.
(l) Automatic Transmission Fluid Temperature Warning Light
(fourwheel drive models)
This light warns that the automatic trans-
mission fluid temperature is too high.
If this light comes on while you are driv-
ing, slow down and pull off the road. Stop
the vehicle at a safe place and put the
selector lever in “P”. With the engine id-
ling, wait until the light goes off. If the
light goes off, you may start the vehicle
again. If the light does not go off, call a
Toyota dealer or qualified repair shop for
assistance. (m) Low Windshield Washer Fluid Level
Warning Light
This light warns that the windshield wash-
er fluid level is too low. Add washer fluid
at your earliest opportunity. (For instruc-
tions, see “Adding washer fluid” in Section
7 −3.)
(n) Key Reminder Buzzer
This buzzer reminds you to remove the
key when you open the driver ’s door with
the ignition key in the “ACC” or “LOCK”
position.
(o) Fourwheel drive system warning buzzer
This buzzer reminds you that the transfer
mode is not selected correctly.
If the buzzer sounds when you shift the
transfer from “2WD” to “4HI”, “4LO” to
“4HI”, “4HI” to “4LO”, or “4LO” to “2WD”
mode, follow the instructions in “Four −
wheel drive system” in Section 1 −6.

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Before starting the engine, be sure to fol-
low the instructions in “(a) Before crank-
ing”.
Normal starting procedure
The multiport fuel injection system/sequen-
tial multiport fuel injection system in your
engine automatically controls the proper
air−fuel mixture for starting. You can start
a cold or hot engine as follows:
1. 5VZ −FE engine—With your foot off the
accelerator pedal, crank the engine by
turning the ignition key to “START”
position. Release it when the engine
starts.
2UZ− FE engine—With your foot off the
accelerator pedal, turn the ignition key
to “START” position, then release it.
2. After the engine runs for about 10 se- conds, you are ready to drive.
If the weather is below freezing, let the
engine warm up for a few minutes before
driving.
If the engine stalls...
Simply restart it, using the correct proce-
dure given in normal starting.
If the engine will not start...
See “If your vehicle will not start” in Sec-
tion 4.NOTICE
 5VZFE engine only—Do not crank
for more than 30 seconds at a time.
This may overheat the starter and
wiring systems.
 Do not race a cold engine.
 If the engine becomes difficult to
start or stalls frequently, have the
engine checked immediately.
Always slow down in gusty crosswinds.
This will allow you much better control.
Drive slowly onto curbs and, if pos-
sible, at a right angle. Avoid driving
onto high, sharp −edged objects and
other road hazards. Failure to do so
can lead to severe tire damage such
as a tire burst.
Drive slowly when passing over bumps
or travelling on a bumpy road. Other-
wise, the impact could cause severe
damage to the tires and/or wheels.
When parking on a hill, turn the front
wheels until they touch the curb so
that the vehicle will not roll. Apply the
parking brake, and place the transmis-
sion in “P” (automatic) or in first or
reverse (manual). If necessary, block
the wheels.
(b) Starting the engine Tips for driving in various
conditions

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TIRES
Ensure that your vehicle’s tires are
properly inflated. See Section 7 −2 and
Section 8 for instructions.
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.
4pin connector
7pin connector
TOWING CONNECTOR FOR TRAILER
LIGHTS
Your vehicle is equipped with a wire
harness stored in the rear end under
body. Some models are fitted with a
socket for trailer lights under the rear
bumper. Use either of them to connect
and operate the trailer lights. However,
the trailer lights must comply with fed-
eral, state/provincial and local regula-
tions. See your local recreational ve-
hicle dealer or rental agency for the
correct type of wiring and relays for
your trailer. Check for correct operation
of the turn signals and stop lights each
time you hitch up. Direct splicing may
damage your vehicle’s electrical system
and cause a malfunction of your lights.
7 −pin connector (with towing pack-
age)—This can be also connected to
the trailer brake and trailer sub battery.

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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)