2004 TOYOTA TUNDRA wiring

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2004 TUNDRA from Sep. ’03 Prod. (OM34426U)
When the seat belt pretensioners are acti-
vated, an operating noise may be heard
and a small amount of non −toxic gas may
be released. This does not indicate that
a fire is occurring. This gas is normally
harmless.
Once the seat belt pretensioners have
been activated, the seat belt retractors
remain locked.
CAUTION
Do not modify, remove, strike or open
the seat belt pretensioner assemblies,
airbag sensor or surrounding area or
wiring. Failure to follow these instruc-
tions may prevent the seat belt pre-
tensioners from activating correctly,
cause sudden operation of the system
or disable the system, which could
result in death or serious injury. Con-
sult your Toyota dealer about any re-
pair and modification.
NOTICE
Do not perform any of the following
changes without consulting your
Toyota dealer. Such changes can
interfere with proper operation of the
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 indicator comes on when the igni-
tion key is turned to the “ON” position.
It goes off after about 6 seconds. This
means the seat belt pretensioners are
operating properly.
This warning light system monitors the
airbag sensor assembly, front airbag sen-
sors, seat belt pretensioner assemblies,
inflators, warning light, interconnecting wir-
ing and power sources. (For details, see
“Service reminder indicators and warning
buzzers” in Section 1 −6.)

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2004 TUNDRA from Sep. ’03 Prod. (OM34426U)
(i) “VSC TRAC” Warning Light
The light warns that there is a problem
somewhere in the following.
Vehicle stability control system
Traction control system
“AUTO LSD” system
The light will come on when the ignition
key turned to “ON”, and will go off after
a few seconds.
It is not a malfunction that the warning
light may stay on for 60 seconds after the
ignition key is turned to the “ON” position.
Depressing the brake pedal repeatedly
may turn on the lights. It is normal if they
go out after a few seconds.
There is no problem when the “VSC
TRAC” warning light comes on when the
brake actuator temperature becomes high.
If the light comes on while driving, the
above mentioned systems do not work.
However, as the brakes operate normally
when applied, it is no problem to continue
your driving. In the following cases, contact your Toyota
dealer:
The warning light does not come on
after the ignition key is turned to “ON”.
The warning light remains on after the
ignition key is turned to “ON”.
The warning light comes on while driv-
ing.
(j) Open Door Warning Light
This light remains on until all the doors
are completely closed.
(k) 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.
(l) 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.

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2004 TUNDRA from Sep. ’03 Prod. (OM34426U)
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:
5VZ− FE engine—With your foot off the ac-
celerator pedal, crank the engine by turn-
ing 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.
Engine should be warmed up by driving,
not in idle. For warming up, drive with
smoothly turning engine until engine cool-
ant temperature is within normal range.
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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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. BREAKIN SCHEDULE
Toyota recommends that you do not
tow a trailer with a new vehicle or a
vehicle with any new power train com-
ponent (engine, transmission, differen-
tial, wheel bearings, etc.) for the first
800 km (500 miles) of driving.
MAINTENANCE
If you tow a trailer, your vehicle will
require more frequent maintenance due
to the additional load. For this informa-
tion, please refer to the scheduled
maintenance information in the “Sched-
uled Maintenance Guide” or “Owner ’s
Manual Supplement”.
Retighten all fixing bolts of the towing
ball and bracket after approximately
1000 km (600 miles) of trailer driving.
PRETOWING SAFETY CHECK
Check that your vehicle remains level
when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle has
an abnormal nose −up or nose −down
condition, and check for improper
tongue load, overload, worn suspension
or other possible causes.
Make sure the trailer cargo is securely
loaded so that it cannot shift.

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2004 TUNDRA from Sep. ’03 Prod. (OM34426U)
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 ignition key to
“START” with the accelerator pedal fully
depressed. Keep the key and accelerator
pedal in these positions for 15 seconds
and release 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)