ECU TOYOTA SIENNA 2001 Service Manual

01 SIENNA_U (L/O0008)
2432001 MY SIENNA (OM45406U)
Weight carrying hitch
Without towing package
90 kg (200 lb.)
With towing package
158 kg (350 lb.)
Weight distributing hitch
With towing package
238 kg (525 lb.)
Never load the trailer with more
weight in the back than in the
front. About 60% of the trailer load
should be in the front half of the
trailer and the remaining 40% in the
rear.
HITCHES
If you wish to install a trailer hitch, you
should consult with your Toyota dealer.
Use only a hitch recommended by the
hitch manufacturer and the one which
conforms to the total trailer weight
requirement.
The hitch must be bolted securely to
the vehicle frame and installed accord-
ing to the hitch manufacturer ’s instruc-
tions.
The hitch ball and king pin should have
a light coat of grease.
Toyota recommends removing the trail-
er hitch whenever you are not towing
a trailer to reduce the possibility of
additional damage caused by the hitch
if your vehicle is struck from behind.
After removing the hitch, seal any
mounting holes in the vehicle body to
prevent entry of pollutants such as ex-
haust fumes, dirt, water, etc.
NOTICE
Do not use axle−mounted hitches as
they can cause damage to the axle
housing, wheel bearings, wheels or
tires. Also, never install a hitch which
may interfere with the normal function
of an Energy Absorbing Bumper, if so
equipped.
BRAKES AND SAFETY CHAINS
Toyota recommends trailers with
brakes that conform to any applica-
ble federal and state/provincial regu-
lations.
A safety chain must always be used
between the towing vehicle and the
trailer. Leave sufficient slack in the
chain for turns. The chain should
cross under the trailer tongue to
prevent the tongue from dropping to
the ground in case it becomes dam-
aged or separated. For correct safety
chain procedures, follow the hitch or
trailer manufacturer ’s recommenda-
tions.
CAUTION
If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.
Never tap into your vehicle’s hy-
draulic system as it would lower its
braking effectiveness.
Never tow a trailer without using a
safety chain securely attached to
both the trailer and the vehicle. If
damage occurs to the coupling unit
or hitch ball, there is danger of the
trailer wandering over into another
lane.
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01 SIENNA_U (L/O0008)
2442001 MY SIENNA (OM45406U)
TIRES
Ensure that your vehicle’s tires are
properly inflated. Adjust the tire pres-
sure to the recommended cold tire
pressure indicated below (see Section
7−2 for instructions.):
Tire pressure, kPa (kgf/cm
2 or bar, psi)
240 (2.4, 35)
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.
TRAILER LIGHTS
Trailer lights must comply with federal,
state/provincial and local regulations.
See your local recreational vehicle
dealer or rental agency for the correct
type of wiring and relays for your trail-
er. Check for correct operation of the
turn signals and stop lights each time
you hitch up. Direct splicing may dam-
age your vehicle’s electrical system
and cause a malfunction of your lights.BREAK−IN 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 bearing, 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
information, please refer to the
scheduled maintenance information in
the “Scheduled 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.
PRE−TOWING 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.
Check that your rear view mirrors con-
form to any applicable federal, state/
provincial or local regulations. If not,
install the rear view mirrors required
for towing purpose.
TRAILER TOWING TIPS
When towing a trailer, your vehicle will
handle differently than when not tow-
ing. The three main causes of vehicle−
trailer accidents are driver error, exces-
sive speed and improper trailer loading.
Keep these in mind when towing:
Before starting out, check operation of
the lights and all vehicle−trailer connec-
tions. After driving a short distance,
stop and recheck the lights and con-
nections. Before actually towing a trail-
er, practice turning, stopping and back-
ing with a trailer in an area away from
traffic until you learn the feel.
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01 SIENNA_U (L/O0008)
2572001 MY SIENNA (OM45406U)
1. Get the required tools and spare
tire.
1. Jack
2. Jack handle
3. Wheel nut wrench
4. Spare tire
To prepare yourself for an emergency, you
should familiarize yourself with the use of
the jack, each of the tools and their stor-
age locations.
Turn the jack joint by hand.
To remove: Turn the joint in direction 1
until the jack is free.
To store: Turn the joint in direction 2 until
the jack is firmly secured to prevent it
flying forward during a collision or sudden
braking.To remove the spare tire;
Open the back door and you will find the
spare tire clamp bolt near the back door
latch.
1. Loosen the spare tire clamp bolt by
turning it counterclockwise with the
wheel nut wrench.
2. After the tire is lowered completely to
the ground, remove the holding brack-
et.
Compact spare tire—
When storing the spare tire, put it in place
with the inner side of the wheel facing up.
Except compact spare tire—
When storing the spare tire, put it in place
with the outer side of the wheel facing up.
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01 SIENNA_U (L/O0008)
2582001 MY SIENNA (OM45406U)
Then secure the tire by repeating the
above removal steps in reverse order to
prevent it from flying forward during a
collision or sudden braking.
Make sure to pull the tire straight up with-
out catching on any other part.
Do not overtighten the bolt. Stop turning
it when you begin to feel resistance on
your hand.
After storing the tire, make sure it is se-
curely locked by pushing it forward and
rearward.
NOTICE
To secure spare tire clamp bolt:
Do not use impact wrench, but
wheel nut wrench.
Tighten the spare tire clamp bolt to
hold the spare wheel carrier by the
hook securely.
—Blocking the wheel
2. Block the wheel diagonally opposite
the flat tire to keep the vehicle from
rolling when it is jacked up.
When blocking the wheel, place a wheel
block from the front for the front wheels
or from the rear for the rear wheels.
—Removing wheel ornament
Steel wheels
Aluminium wheels
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01 SIENNA_U (L/O0008)
2612001 MY SIENNA (OM45406U)
Before putting on wheels, remove any cor-
rosion on the mounting surfaces with a
wire brush or such. Installation of wheels
without good metal−to−metal contact at the
mounting surface can cause wheel nuts to
loosen and eventually cause a wheel to
come off while driving. Therefore after the
first 1600 km (1000 miles), check to see
that the wheel nuts are tight.
—Reinstalling wheel nuts
8. Reinstall all the wheel nuts finger
tight.
Reinstall the wheel nuts (tapered end in-
ward) and tighten them as much as you
can by hand. Press back on the tire and
see if you can tighten them more.
—Lowering your vehicle
9. Lower the vehicle completely and
tighten the wheel nuts.
Turn the jack handle counterclockwise to
lower the vehicle.
Use only the wheel nut wrench to tighten
the nuts. Do not use other tools or any
additional leverage other than your hands,
such as a hammer, pipe or your foot.
Make sure the wrench is securely en-
gaged over the nut.
Tighten each nut a little at a time in the
order shown. Repeat the process until all
the nuts are tight.
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01 SIENNA_U (L/O0008)
2632001 MY SIENNA (OM45406U)
—After changing wheels
11. Check the air pressure of the re-
placed tire.
Adjust the air pressure to the specification
designed in Section 8. If the pressure is
lower, drive slowly to the nearest service
station and fill to the correct pressure.
Do not forget to reinstall the tire inflation
valve cap as dirt and moisture could get
into the valve core and possibly cause air
leakage. If the cap is missing, have a new
one put on as soon as possible.
12. Restow all the tools, jack and flat
tire securely.
As soon after changing wheels as pos-
sible, tighten the wheel nuts to the torque
specified in Section 8 with a torque
wrench. Have a technician repair the flat
tire.
Vehicles with a spare tire of the same
size as the installed tires—
13. Push the tire pressure warning sys-
tem reset switch.
Initial adjustment of the tire pressure
warning system is necessary after you
have replaced your tires or wheels. See
“Tire pressure warning system” in Section
1−6.CAUTION
Before driving, make sure all the
tools, jack and flat tire are securely
in place in their storage location to
reduce the possibility of personal in-
jury during a collision or sudden
braking.
(a) Towing with wheel lift type truck—
—From front
—From rear
(b) Using flat bed truck
If your vehicle needs to be
towed—
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01 SIENNA_U (L/O0008)
2652001 MY SIENNA (OM45406U)
—Emergency towing
Front
Rear
If towing is necessary, we recommend
you to have it done by your Toyota
dealer or a commercial tow truck ser-
vice.
If towing service is not available in an
emergency, your vehicle may be tempo-
rarily towed by a cable or chain se-
cured to one of the emergency towing
eyelets under the vehicle. Use extreme
caution when towing vehicles.
NOTICE
Only use specified towing eyelet;
otherwise your vehicle may be dam-
aged.
A driver must be in the vehicle to steer
it and operate the brakes.
Towing in this manner may be done only
on hard−surfaced roads for a short dis-
tance and at low speeds. Also, the
wheels, axles, drive train, steering and
brakes must all be in good condition.
CAUTION
Use extreme caution when towing ve-
hicles. Avoid sudden starts or erratic
driving maneuvers which would place
excessive stress on the emergency
towing eyelets and towing cable or
chain. The eyelets and towing cable
or chain may break and cause serious
injury or damage.
NOTICE
Use only a cable or chain specifically
intended for use in towing vehicles.
Securely fasten the cable or chain to
the towing eyelets provided.
Before towing, release the parking brake
and put the transmission in “N”. The key
must be in “ACC” (engine off) or “ON”
(engine running).
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.
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01 SIENNA_U (L/O0008)
2772001 MY SIENNA (OM45406U)
If you are a skilled do−it−yourself mechan-
ic, the Toyota service manuals are recom-
mended. Please be aware that do−it−your-
self maintenance can affect your warranty
coverage. See “Owner ’s Warranty Informa-
tion Booklet” or “Owner ’s Manual Supple-
ment” for the details.
General maintenance
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
Section 7−2 for additional information.Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See Section 7−2 for
additional information. When checking the
tires, make sure no nuts are missing, and
check the nuts for looseness. 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 Section
7−2 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.
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.
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01 SIENNA_U (L/O0008)
2782001 MY SIENNA (OM45406U)
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 rear seatbacks
and detachable rear seats, 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.
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 pedal 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.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 Section 7−3 for additional in-
formation.
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 Section 7−2 for additional information.
Battery electrolyte level
Make sure the electrolyte level of all bat-
tery cells is between upper and lower lev-
el lines on the case. Add only distilled
water when replenishing. See Section 7−3
for additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See Section 7−2 for additional information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See Section 7−2 for addi-
tional information.
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01 SIENNA_U (L/O0008)
3172001 MY SIENNA (OM45406U)
Instrument panel
9. HORN 10 A: Horn, theft deterrent sys-
tem
10. HAZARD 10 A: Emergency flashers
11. AM2 30 A: “IGN” and “STARTER”
fuses
12. HEAD (LH) 15 A: Left−hand headlight
(high beam)
13. RADIO NO.1 20 A: Car audio system
Instrument panel
14. DOME 10 A: Clock, personal lights,
vanity mirror lights, door courtesy
lights, luggage compartment light, open
door warning light, ignition switch light,
theft deterrent system, daytime running
light system, interior lights, air condi-
tioning system, wireless remote control,
garage door opener
15. ECU−B 10 A: Cruise control system,
SRS warning light, power sliding door
16. FOG 20 A: Front fog lights
17. ABS NO.3 25 A: Vehicle skid control
system18. ABS NO.2 25 A: Vehicle skid control
system
19. H−LP LH (LO) 10 A: Left−hand head-
light (low beam)
20. H−LP RH (LO) 10 A: Right−hand head-
light (low beam)
21. ABS NO.4 5 A: Vehicle skid control
system
22. HEATER 10 A: Air conditioning system,
rear window defogger
23. GAUGE 10 A: Gauges and meters,
service reminder indicators and warning
buzzers (except discharge and open
door warning light), power windows,
daytime running light system, back−up
lights, power sliding door, auto anti−
glare inside rear view mirror, compass
24. WIPER 25 A: Windshield wipers and
washer, rear window wiper and washer
25. MIRROR−HEATER 10 A: Multiport fuel
injection system/sequential multiport
fuel injection system, outside rear view
mirror defogger
26. ECU−IG 15 A: Cruise control system,
anti−lock brake system, vehicle skid
control system, locking with wireless
remote control system, theft deterrent
system
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