ECU TOYOTA SIENNA 1999 Owner's Guide

name. SIENNA (45403U)
189
Brake pad wear limit indicators
The brake pad wear limit indicators on
your disc brakes give a warning noise
when the brake pads are worn to where
replacement is required.
If you hear a squealing or scraping noise
while driving, have the brake pads
checked and replaced by your Toyota
dealer as soon as possible. Expensive ro-
tor damage can result if the pads are not
replaced when necessary.
Luggage stowage precautions
When stowing luggage or cargo in the
vehicle, observe the following:
Put luggage or cargo in the luggage
compartment when at all possible. Be
sure all items are secured in place.
Be careful to keep the vehicle bal-
anced. Locating the weight as far for-
ward as possible helps maintain bal-
ance.
For better fuel economy, do not carry
unneeded weight.
CAUTION
To prevent luggage or packages
from sliding forward during braking,
do not stack anything in the lug-
gage compartment higher than the
seatbacks. Keep luggage or pack-
ages low, as close to the floor as
possible.
Never allow anyone to ride in the
luggage compartment. It is not de-
signed for passengers. They should
ride in their seats with their seat
belts properly fastened. Otherwise,
they are much more likely to suffer
serious bodily injury, in the event
of sudden braking or a collision.
Do not drive with objects left on
top of the instrument panel. They
may interfere with the driver’s field
of view. Or they may move during
sharp vehicle acceleration or turn-
ing, and impair the driver’s control
of the vehicle. In an accident they
may injure the vehicle occupants.
NOTICE
Do not load the vehicle beyond the
vehicle capacity weight specified in
Part 8.
ProCarManuals.com

name. SIENNA (45403U)
190
The roof luggage carrier consists of
roof rails (1) attached to the roof and
sliding crossrails (2).
To adjust the positions of crossrails, do
this.
1. Turn the knobs counterclockwise to
loosen the crossrails.
2. Slide the crossrails to the desired posi-
tion for loading the luggages of various
sizes.
3. After adjusting, be sure to tighten the
crossrails by turning knobs clockwise.
Follow the manufacture’s instructions and
precautions when installing the attach-
ments or their equivalent.
CAUTION
When you load cargo on the roof lug-
gage carrier, observe the following:
Place the cargo so that its weight
is distributed evenly between the
front and rear axles.
If loading long or wide cargo, never
exceed the vehicle overall length or
width. (See ”Dimensions” in Part 8
for information on your vehicle
overall length and width.)
Before driving, make sure the cargo
is securely fastened on the roof
luggage carrier.
Avoid sudden starts, sharp turns or
sudden braking.
If driving for a long distance, on
rough roads, or at high speeds,
stop the vehicle now and then dur-
ing the trip to make sure the cargo
remains in its place.
Do not exceed 50 kg (110 lb.) cargo
weight on the roof rails. However,
if the allowable cargo weight of the
cross rails is under 50 kg (110 lb.)
observe the load limit.
NOTICE
When loading the luggages, be careful
not to scratch the surface of the
moon roof.
Roof luggage carrier
ProCarManuals.com

name. SIENNA (45403U)
197
CAUTION
Before driving off, make sure that
the parking brake is fully released
and the parking brake reminder
light is off.
Do not leave your vehicle unat-
tended while the engine is running.
Do not rest your foot on the brake
pedal while driving. It can cause
dangerous overheating, needless
wear, and poor fuel economy.
To drive down a long or steep hill,
reduce your speed and downshift.
Remember, if you ride the brakes
excessively, they may overheat and
not work properly.
Be careful when accelerating, up-
shifting, downshifting or braking on
a slippery surface. Sudden accelera-
tion or engine braking could cause
the vehicle to spin or skid.
Do not drive in excess of the speed
limit. Even if the legal speed limit
permits it, do not drive over 140
km/h (85 mph) unless your vehicle
has high−speed capability tires.
Driving over 140 km/h (85 mph) may
result in tire failure, loss of control
and possible injury. Be sure to con-
sult a tire dealer to determine
whether the tires on your vehicle
are high−speed capability tires or
not before driving at such speeds.
Do not continue normal driving
when the brakes are wet. If they are
wet, your vehicle will require a
longer stopping distance, and it
may pull to one side when the
brakes are applied. Also, the park-
ing brake will not hold the vehicle
securely.
Winter driving tips
Make sure you have a proper freeze
protection of engine coolant.
Your coolant must contain ethylene−glycol
type coolant for a proper corrosion
protection of aluminum components. Use
”Toyota Long Life Coolant” or equivalent.
See Chapter 7−2 for details about coolant
type selection.
NOTICE
Do not use alcohol type antifreeze or
plain water alone.
When it is extremely cold, we recommend
to use 60% solution for your Toyota, to
provide protection down to about −50°C
(−58°F). Do not use more than 70% solu-
tion for better coolant performance.
Check the condition of the battery and
cables.
Cold temperatures reduce the capacity of
any battery, so it must be in top shape
to provide enough power for winter start-
ing. Chapter 7−3 tells you how to visually
inspect the battery. Your Toyota dealer
and most service stations will be pleased
to check the level of charge.
ProCarManuals.com

name. SIENNA (45403U)
200
Total trailer weight Tongue load
Tongue load
Total trailer weight9 to 11%
(∗
1)
or 15% (∗
2)100 = 
The trailer cargo load should be
distributed so that the tongue load
is 9 to 11% for weight carrying
hitch
(∗
1) or 15% for weight distrib-
ut i ng hi t ch (∗
2) of the total trailer
weight, not exceeding the maximum
load of the following.
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.
ProCarManuals.com

name. SIENNA (45403U)
201 
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.
TIRES
Ensure that your vehicle’s tires are
properly inflated. Adjust the tire pres-
sure to the recommended cold tire
pressure indicated below (see Chapter
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 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.
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.
ProCarManuals.com

name. SIENNA (45403U)
214
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.
—Required tools and spare
tire
ProCarManuals.com

name. SIENNA (45403U)
215
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.
—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
ProCarManuals.com

name. SIENNA (45403U)
218
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.
ProCarManuals.com

name. SIENNA (45403U)
220
—After changing wheels
11. Check the air pressure of the re-
placed tire.
Adjust the air pressure to the specification
designed in Part 8. If the pressure is low-
er, drive slowly to the nearest service sta-
tion 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 Part 8 with a torque wrench
and 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 Chapter
1−8.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—
ProCarManuals.com

name. SIENNA (45403U)
222
—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.
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.
ProCarManuals.com