2002 TOYOTA PRIUS low oil pressure

5
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
Anti −lock brake system warning light∗
1
Headlight high beam indicator light
Headlight indicator light Turn signal indicator lights SRS warning light
∗1

94
(e) Malfunction Indicator Lamp
This lamp comes on when the ignition
key is turned to the “ON” position and
goes off after the engine starts. This
means that the warning light system is
operating properly.
If the lamp remains on or the lamp
comes on while driving, first check the
following:
Empty fuel tank
If the fuel tank is empty, refuel immedi-
ately.
This case is a temporary malfunction. The
malfunction indicator lamp will go off after
taking several driving trips.
If the lamp will not go off even after
several trips, contact your Toyota deal-
er as soon as possible.
There is a problem somewhere in the
hybrid system or warning light system
itself.
Contact your Toyota dealer as soon as
possible to service the vehicle. Emissions inspection and maintenance
(I/M) programs
Your vehicle may not pass a state emis-
sion inspection if the malfunction indicator
lamp remains on. Contact your Toyota
dealer to check your vehicle’s emission
control system and OBD (On
−Board Diag-
nostics) system before taking your vehicle
for the inspection.
For details, see “Emissions inspection and
maintenance (I/M) programs” on page 198
in Section 7.
(f) Master Warning Light
()
If the master warning light comes on, the
warning light for the faulty system is high-
lighted or the message such as “When
you park your car, make sure you shift to
Park P.” and “The batteries will not charge
if the shifter is in N” appears on the mul-
ti −information display. (See “Service re-
minder indicators and warning buzzers—
—Multi −information display” on page 97
in this section or “Precautions for use” on
page 12 in Section 1 −2 or “Fuel gauge”
on page 88 in Section 2− 4 for instruc-
tions.) (g) Output Control Warning Light
()
This light comes on when the ignition
switch is on. It goes off when the electric
motor is ready to run.
The warning light comes on when the hy-
brid vehicle battery temperature is low or
high, or the hybrid vehicle battery capacity
is decreased with the selector lever at “R”
during driving. If the light comes on, the
power will be limited. Drive your vehicle
without hard acceleration.
(h) Low Engine Oil Pressure Warning
Light
This light warns that the engine oil pres-
sure is too low.
If it flickers or stays on while you are
driving, pull off the road to a safe place
and stop the engine immediately. Call a
Toyota dealer or qualified repair shop for
assistance.
The light may occasionally flicker when
the engine is idling or it may come on
briefly after a hard stop. There is no
cause for concern if it then goes out when
the engine is accelerated slightly.
The light may come on when the oil level
is extremely low. It is not designed to
indicate low oil level, and the oil level
must be checked using the level dipstick.

151
FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining the engine in proper working order.
ENGINE OIL CONSUMPTION
It is normal that an engine should con-
sume some engine oil during normal
engine operation. The causes of oil
consumption in a normal engine are as
follows.
Oil is used to lubricate pistons, piston
rings and cylinders. A thin film of oil
is left on the cylinder wall when a
piston moves downwards in the cylin-
der. High negative pressure generated
when the vehicle is decelerating sucks
some of this oil into the combustion
chamber. This oil as well as some part
of the oil film left on the cylinder wall
is burned by the high temperature com-
bustion gases during the combustion
process.
Oil is also used to lubricate the stems
of the intake valves. Some of this oil
is sucked into the combustion chamber
together with the intake air and is
burned along with the fuel. High tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems.
The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by high −speed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately. As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an expressway, making it
appear that oil is excessively consumed
after driving at high speeds.
IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
Facts about engine oil
consumption

166
Improving fuel economy is easy−just take
it easy. It will help make your vehicle last
longer, too. Here are some specific tips
on how to save money on both fuel and
repairs:
Keep your tires inflated at the cor-
rect pressure. Underinflation causes
tire wear and wastes fuel. See page
214 in Section 8 −2 for instructions.
Do not carry unneeded weight in
your vehicle. Excess weight puts a
heavier load on the engine, causing
greater fuel consumption.
Accelerate slowly and smoothly.
Avoid jackrabbit starts.
Avoid continuous speeding up and
slowing down. Stop−and− go driving
wastes power.
Avoid unnecessary stopping and
braking. Maintain a steady pace. Try
to time the traffic signals so you only
need to stop as little as possible or
take advantage of through streets to
avoid traffic lights. Keep a proper dis-
tance from other vehicles to avoid sud-
den braking. This will also reduce wear
on your brakes.
Avoid heavy traffic or traffic jams
whenever possible.
Do not rest your foot on brake ped-
al. This causes premature wear, over-
heating and poor fuel economy.
Maintain a moderate speed on high-
ways. The faster you drive, the greater
the fuel consumption. By reducing your
speed, you will cut down on fuel con-
sumption.
Keep the front wheels in proper
alignment. Avoid hitting the curb and
slow down on rough roads. Improper
alignment not only causes faster tire
wear but also puts an extra load on
the engine, which, in turn, wastes fuel.
Keep the bottom of your vehicle free
from mud, etc. This not only lessens
weight but also helps prevent corro-
sion.
Keep your vehicle tunedup and in
top shape . A dirty air cleaner, improp-
er valve clearance, dirty plugs, dirty oil
and grease, brakes not adjusted, etc.
all lower engine performance and con-
tribute to poor fuel economy. For longer
life of all parts and lower operating
costs, keep all maintenance work on
schedule, and if you often drive under
severe conditions, see that your ve-
hicle receives more frequent mainte-
nance.
CAUTION
Never turn off the hybrid system to
coast down hills. Your power steering
and brake booster will not function
without the hybrid system running.
Also, the emission control system op-
erates properly only when the hybrid
system is running.
How to save fuel and make
your vehicle last longer, too

172
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 168.
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 driving If your vehicle overheats

195
If you are a skilled do−it−yourself
mechanic, the Toyota service manuals are
recommended. Please be aware that
do− it−yourself maintenance can affect your
warranty coverage. See ”Owner ’s Warranty
Information Booklet” or ”Owner ’s Manual
Supplement” 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
page 214 in Section 8 −2 for additional
information. Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See Section 8
−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 page 216
in Section 8− 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 and trunk operate
smoothly and all latches lock securely.
Make sure the engine hood secondary
latch secures the hood from opening when
the primary latch is released.