2003 TOYOTA PRIUS engine coolant

5
4.Indicator symbols on the instrument panel and Multiinformation display
or
orBrake system warning light∗1
Discharge warning light∗1
Seat belt reminder light∗1
Front passenger ’s seat belt reminder light∗1
Malfunction indicator lamp∗1
Low coolant temperature indicator light
(in blue)∗1
High coolant temperature warning light (in red)∗1
Low fuel level indicator light∗1
Low engine oil pressure warning light∗1
Open door warning light∗1
Master warning light∗1
Antilock brake system warning light∗1
Headlight high beam indicator light
Headlight indicator light Turn signal indicator lights SRS warning light
∗1

12
The hybrid system automatically con-
trols the level of electrical power re-
maining in the hybrid vehicle battery.
With the selector lever in a position
other than “N”, electricity is generated
and charging occurs when the level of
electrical power in the hybrid vehicle
battery decreases. It is unnecessary to
charge the hybrid vehicle battery from
outside.
INFORMATION:
The gasoline engine starts and stops
automatically. (It stops during a low
load driving, deceleration or when the
vehicle stopped.)
If the “READY” light remains on, you
can start your vehicle using the electric
motor even with the gasoline engine
stopped.
The gasoline engine may not stop auto-
matically in the following conditions:
 During under gasoline engine warm
up
 During hybrid vehicle battery charg-
ing
 When the air conditioning is used in
the “MAX” mode, the gasoline engine
is frequently used. If the output control warning light ()
comes on in the instrument cluster, the
hybrid vehicle battery temperature is
low or high, or the hybrid vehicle bat-
tery capacity is decreased with the se-
lector lever at “R” during driving. As it
does not indicate the failure of the sys-
tem, you can continue driving but avoid
hard acceleration because the power is
insufficient (which is caused by the bat-
tery power deterioration).
The vehicle runs in combination with
the gasoline and electric power. Pay
special attention to the following items.
Be careful of a high voltage and high
temperature.
Your vehicle is equipped with the orange
colored cables connected to the hybrid
vehicle battery which contain a high volt-
age (about 300 V) and to other high volt-
age parts.
CAUTION
Do not touch or come in contact with
orange cables or battery terminals.
Electric shock may cause serious in-
jury or death. Read all caution labels.
A electric motor, coolant radiator and
some other parts reach high temperature
when you are driving. Caution labels are
applied to these parts. Carefully observe
the instructions on these caution labels.
10.Precautions for use

168
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 highspeed capability tires.
Driving over 140 km/h (85 mph)
may result in tire failure, loss of
control and possible injury. Be sure
to consult a tire dealer to determine
whether the tires on your vehicle
are highspeed 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 lon-
ger stopping distance, and it may
pull to one side when the brakes
are applied. Also, the parking brake
will not hold the vehicle securely.
Make sure you have a proper freeze
protection of coolant.
Your coolant must contain ethyleneglycol
type coolant for a proper corrosion
protection of aluminum components. Use
“Toyota Genuine Long Life Coolant” or
equivalent.
See 217 page in Section 82 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 auxiliary
battery and cables.
Cold temperatures reduce the capacity of
any auxiliary battery, so it must be in top
shape to provide enough power for winter
starting. Section 83 tells you how to
visually inspect the auxiliary battery. Your
Toyota dealer will be pleased to check the
level of charge. Make sure the engine oil viscosity is
suitable for the cold weather.
See 215 page in Section 82 for recom-
mended viscosity. Leaving a heavy sum-
mer oil in your vehicle during winter
months may cause harder starting. If you
are not sure about which oil to use, call
your Toyota dealer—he will be pleased to
help.
Keep the door locks from freezing.
Squirt lock deicer or glycerine into the
locks to keep them from freezing.
Use a washer fluid containing an anti
freeze solution.
This product is available at your Toyota
dealer and most auto parts stores. Follow
the manufacturer ’s directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any
other substitute as washer fluid be-
cause it may damage your vehicle’s
paint.
Winter driving tips124.

176
If your hybrid system stalls while driving...1. Reduce your speed gradually, keeping a straight line. Move cautiously off the
road to a safe place.
2. Turn on your emergency flashers.
3. Turn the ignition switch to ”OFF” posi- tion, and try starting the hybrid system
again.
If the hybrid system will not start, see “If
your vehicle will not start” on page 172.
CAUTION
If the hybrid system is not operating,
the power assist for the brakes and
steering will not work so steering and
braking will be much harder than usu-
al.
If your high coolant temperature warn-
ing light comes on, if you experience a
loss of power, or if you hear a loud
knocking or pinging noise, the hybrid
system has probably overheated. You
should follow this procedure... 1. Pull safely off the road, stop the ve- hicle and turn on your emergency
flashers. Put the transmission in “P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the radiator or reservoir, stop the hybrid
system. Wait until the steam subsides
before opening the hood. If there is no
coolant boiling over or steam, leave the
hybrid system running and make sure
the electric cooling fan is operating. If
it is not, turn the ignition off.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
3. Look for obvious coolant leaks from theradiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the hybrid system is running,
keep hands and clothing away from
the moving fan and engine drive
belts.
4. If the coolant is leaking, stop the hy-brid system immediately. Call a Toyota
dealer for assistance.
5. If there are no obvious leaks, check the coolant reservoir. If it is dry, add
coolant to the reservoir while the hy-
brid system is running. Fill it about half
full.
CAUTION
Do not attempt to remove the radiator
cap when the hybrid system and ra-
diator are hot. Serious injury could
result from scalding hot fluid and
steam blown out under pressure.
If your hybrid system stalls
while driving130. 131.If your vehicle overheats

202
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.
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 front seat controls such as
seat adjusters, seatback recliner, etc. op-
erate smoothly and that all latches lock
securely in any position. Check that the
head restraint move up and down smooth-
ly and that the locks hold securely in any
latched position.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.
Hybrid transaxle ”Park” mechanism
Check the lock release button of the se-
lector lever for proper and smooth opera-
tion. On a safe incline, check that your
vehicle is held securely with the selector
lever in ”P” position and all brakes re-
leased.
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 page 231 in Section 83 for
additional information.
Coolant level
Make sure the coolant level is between
the ”FULL” and ”LOW” lines on the see
through reservoir when the hybrid system
is cold. See page 216 in Section 82 for
additional information.
Radiator, condenser and hoses
Check that the front of the radiator and
condenser are clean and not blocked with
leaves, dirt, or insects. See page 218 in
Section 82 for additional information.

203
Brake fluid level
Make sure the brake fluid level is correct.
See page 218 in Section 82 for addition-
al information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See page 214 in Section
82 for additional information.
Exhaust system
If you notice any change in the sound of
the exhaust or smell exhaust fumes, have
the cause located and corrected immedi-
ately. (See “Engine exhaust cautions” on
page 154 in Section 3.)Be on the alert for changes in perfor-
mance, sounds, and visual tipoffs that
indicate service is needed. Some impor-
tant clues are as follows:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A fluid leak under the vehicle (however,
water dripping from the air conditioning
after use is normal.)
Change in exhaust sound (This may
indicate a dangerous carbon monoxide
leak. Drive with the windows open and
have the exhaust system checked im-
mediately.)
Flatlooking tire; excessive tire squeal
when cornering; uneven tire wear
Vehicle pulls to one side when driving
straight on a level road
Strange noises related to suspension
movement
Loss of brake effectiveness; spongy
feeling brake pedal; pedal almost
touches floor; vehicle pulls to one side
when braking
Coolant temperature continually higher
than normalIf you notice any of these clues, take your
vehicle to your Toyota dealer as soon as
possible. It probably needs adjustment or
repair.
CAUTION
Do not continue driving with the ve-
hicle unchecked. It could result in se-
rious vehicle damage and possibly
personal injury.
146.Does your vehicle need
repairing?

206
149.Engine compartment overview
1. Engine coolant reservoir
2. Fuse blocks
3. Brake fluid reservoir
4. Engine oil filler cap
5. Inverter reservoir tank
6. Windshield washer fluid tank
7. Radiator and condenser
8. Engine oil level dipstick
9. Auxiliary battery
81p001f

208
If you perform maintenance by yourself,
be sure to follow the correct procedure
given in this Section.
You should be aware that improper or in-
complete servicing may result in operating
problems.
Performing doityourself maintenance
during the warranty period may affect your
warranty coverage. Read the separate
Toyota Warranty statement for details and
suggestions.
This Section gives instructions only for
those items that are relatively easy for an
owner to perform. As explained in Section
7, there are still a number of items that
must be done by a qualified technician
with special tools.
For information on tools and parts for do
ityourself maintenance, see ”Parts and
tools” on page 211 in this Section.
Utmost care should be taken when work-
ing on your vehicle to prevent accidental
injury. Here are a few precautions that
you should be especially careful to ob-
serve:CAUTION
When the hybrid system is on, keep
hands, clothing, and tools away
from the moving fan and engine
drive belts. (Removing rings,
watches, and ties is advisable.)
Right after driving, the engine
compartment—the engine, radiator,
exhaust manifold and spark plug
boots, etc.—will be hot. So be care-
ful not to touch them. Oil, fluids
and spark plugs may also be hot.
If the hybrid system is hot, do not
remove the radiator cap or loosen
the drain plugs to prevent burning
yourself.
Do not smoke, cause sparks or al-
low open flames around fuel or the
batteries. Their fumes are flam-
mable.
When the hybrid system is operat-
ing with the “READY” light on, the
engine is automatically started in
some case. When you inspect the
engine compartment, be sure to
turn the ignition switch to “OFF”
position.
Do not get under your vehicle with
just the body jack supporting it. Al-
ways use automotive jack stands or
other solid supports.
Be sure that the ignition is off if
you work near the electric cooling
fans or radiator grille. With the
ignition on, the electric cooling fans
will automatically start to run if the
engine coolant temperature is high
and/or the air conditioning is on.
Use eye protection whenever you
work on or under your vehicle
where you may be exposed to fly-
ing or falling material, fluid spray,
etc.
Be extremely cautious when work-
ing on the batteries. It contains poi-
sonous and corrosive sulfuric acid
or strong alkali.
Warning: Battery posts, terminals and
related accessories contain lead and
lead compounds, chemicals known to
the State of California to cause can-
cer and reproductive harm. Wash
hands after handling.
Doityourself service
precautions151.