warning TOYOTA PRIUS 2009 2.G Service Manual

426 5-2. Steps to take in an emergency
PRIUS_U_(OM47614U)
Have the malfunction repaired immediately.After taking the specified steps to correct the suspected problem,
check that the warning light turns off.
Warning lightWarning light/DetailsCorrection procedure
Open door warning light
(warning buzzer)
*2
A door or a back door is
not fully closed.
Check that all doors and the
back door are closed.
Low fuel level warning
light Remaining fuel
(Approximately 3.0 gal.
[11.4 L, 2.5 Imp.gal.] or
less) Refuel the vehicle.
Driver’s seat belt
reminder light (warning
buzzer)
*3
Warns the driver to fasten
his/her seat belt. Fasten the seat belt.
Front passenger’s seat
belt reminder light
(warning buzzer)
*3
Warns the front passen-
ger to fasten his/her seat
belt. Fasten the seat belt.
Tire pressure warning
light
When the light comes on:
Low tire inflation pressure.
Adjust the tire inflation
pressure.
When the light stays on
after blinking for 1 minute:
Malfunction in the tire
pressure warning system. Have the system checked
by your Toyota dealer.

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When trouble arises
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5-2. Steps to take in an emergency
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*1: This warning light is di
splayed on the touch screen.
*2: Open door warning buzzer:

(U.S.A.)
Engine oil replacement
reminder light
Illuminates for about 3 sec-
onds and then flasher for
about 15 seconds:
Engine oil is scheduled to
be changed. Check and the engine oil,
and change if necessary.
Comes on and remains:
Engine oil should be
changed. Check and change the
engine oil.

*1
Hybrid battery warning
light
The hybrid battery voltage
drops when the transmis-
sion is left in “N” position. Push the “P” position
switch.
The hybrid battery is dis-
charged. If this light comes on with
the “READY” light on in this
case, have the system
checked by your Toyota
dealer.

*1
High coolant temperature
warning light Indicates high engine cool-
ant temperature P. 454
Master warning light A buzzer sounds and the
warning light comes on
and flashes to indicate that
the master warning system
has detected a malfunc-
tion. Take appropriate action in
accordance with the mes-
sage displayed on the touch
screen.
Warning lightWarning light/DetailsCorrection procedure

428 5-2. Steps to take in an emergency
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*3:Driver’s and front passenger’s seat belt reminder buzzer:
The driver’s and front passenger’s seat belts reminder sounds to alert the
driver and front passenger that his or her seat belt is not fastened. The
buzzer sounds intermittently for 10 seconds after the vehicle has reached a
speed of at lest 12 mph (20 km/h). Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 20 more seconds.
Have the malfunction repaired immediately. (vehicles with smart
key system)
After taking the specified steps to correct the suspected problem,
check that the warning light turn off.
AlarmWarning lightDetailsCorrection procedure
Interior and
exterior alarm:
One beep
(sounds con-
tinuously)
The driver has
removed the smart key
from the vehicle while
the hybrid system is
not OFF and the shift
lever is in a position
other than “P”.Pressing the “P”
position switch
before removing the
smart key from the
vehicle and turning
the hybrid system
OFF.
Interior alarm:
One beep
Exterior alarm:
3 beeps The driver has
removed the smart key
from the vehicle while
the hybrid system is
not OFF and the shift
lever is in the “P” posi-
tion.
Turn the hybrid sys-
tem OFF and
remove the key
from the vehicle.
A passenger has
removed the smart key
from the vehicle while
the hybrid system is
not OFF. Check whether the
passenger leaving
the vehicle is carry-
ing the smart key.

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5-2. Steps to take in an emergency
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Exterior alarm:
One beep
(sounds for 2
seconds)
The lock button has
been pressed while
the hybrid system is
not OFF and the shift
position is in “P”.
Turn the hybrid sys-
tem OFF.
Interior alarm:
One beep (for 5
seconds) The vehicle’s ID code
detection system has
judged that the smart
key is not present
when the “POWER”
switch is pressed.
Check that the
smart key is in the
vehicle and within
the detection area.
AlarmWarning
lightDetailsCorrection procedure

430 5-2. Steps to take in an emergency
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■If the malfunction indicator lamp comes on while driving
First check the following:
● Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
● Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Toyota dealer
as soon as possible.
■ Power steering warning light
When the voltage is low or drops, the power steering warning light may
come on.
■ SRS warning light
This warning light system monitors the following:
● The airbag sensor assembly
● Front airbag sensors
● The curtain shield airbag sensors
● The side and curtain shield airbag sensor assemblies
● The driver’s seat position sensor
● Driver’s seat belt buckle switch
● The front passenger occupant classification ECU
● The pressure sensor
● The belt tension sensor
● “AIR BAG ON” and “AIR BA G OFF” indicator lights
● Front passenger’s seat belt buckle switch
● The inflators
● The warning light
● The interconnecting wiring and power sources

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5-2. Steps to take in an emergency
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■
Front passenger detection sensor and passenger seat belt reminder
If luggage is placed on the front passenger seat, the front passenger detec-
tion sensor may cause the warning light to flash, even if a passenger is not
sitting in the seat.
■
When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level.
Pushing the tire pressure warning reset switch does not turn off the tire
pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such
as natural air leaks or tire inflation pressure changes caused by temper-
ature. In this case, adjusting the ti re inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with the tire pressure warning
valve and transmitter. If a tire goes flat, the tire pressure warning light will
not turn off even though the flat tire is replaced with the spare tire.
Replace the spare tire with the repair ed tire and adjust the proper tire
inflation pressure. The ti re pressure warning light will turn off after a few
minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following condi-
tions:
(When the condition be comes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmit-
ters are used.
●If the ID code on the tire pressure warning valves and transmitters is
not registered in the tire pressure warning computer.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or
higher.

432 5-2. Steps to take in an emergency
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The tire pressure warning system may be disabled in the following condi-
tions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies
are nearby.
●If a radio set at similar frequencies is in use in the vehicle.
●If a window tint that affects the radio wave signals is installed.
●If there is a lot of snow or ice on the vehicle, in particular around the
wheels or wheel housings.
●If non-genuine Toyota wheels are used (Even if you use Toyota
wheels, the tire pressu re warning system may not work properly with
some types of tires.).
●If tire chains are used.
■If the tire pressure warning light comes on after blinking for 1
minute frequently
If the tire pressure warning light comes on after blinking for 1 minute fre-
quently when the “POWER” switch is turned to ON mode, have it
checked by your Toyota dealer.

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5-2. Steps to take in an emergency
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CAUTION
■
When the power steering warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, firmly
hold and operate it using more force than usual.
■
If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could
cause loss of vehicle control and result in death or serious injury.
● Stop your vehicle in a safe place as soon as possible. Adjust the tire infla-
tion pressure immediately.
● If the tire pressure warning light comes on even after tire inflation pressure
adjustment, it is probable that you have a flat tire. Check the tires. If the
tire is flat, change to the spare tire and have the flat tire repaired by the
nearest Toyota dealer.
● Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you
could lose control of the steering wheel or the brakes.
■
If a blowout or sudden air loss should occur
The tire pressure warning syste m may not activate immediately.

434 5-2. Steps to take in an emergency
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CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly
when cold and inflated to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or tire inflation pressure
label (tire and load information label). (If your vehicle has tires of a differ-
ent size than the size indicated on the vehicle placard or tire inflation
pressure label [tire and load information label], you should determine the
proper tire inflation pr essure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire
pressure monitoring system (TPMS-ti re pressure warning system) that
illuminates a low tire pressure telltal e (tire pressure warning light) when
one or more of your tires is significantly under-inflated. Accordingly,
when the low tire pressu re telltale (tire pressure warning light) illumi-
nates, you should stop and check your tires as soon as possible, and
inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel effi ciency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a sub-
stitute for proper tire main tenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-inflation has not reached the
level to trigger illu mination of the TPMS low tire pressure telltale (tire
pressure warning light).

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5-2. Steps to take in an emergency
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CAUTION
Your vehicle has also been equipped with a TPMS (tire pressure warning
system) malfunction indicator to indi
cate when the system is not operat-
ing properly. The TPMS (tire pressure warning system) malfunction indi-
cator is combined with the low tire pressure telltale (tire pressure
warning light). When the system det ects a malfunction, the telltale will
flash for approximately one minute an d then remain continuously illumi-
nated. This sequence will continue upon subsequent vehicle start-ups as
long as the malfunction exists. When the malfunction indi cator is illumi-
nated, the system may not be able to detect or signal low tire pressure
as intended.
TPMS (tire pressure warning system) malfunctions may occur for a vari-
ety of reasons, including the installati on of replacement or alternate tires
or wheels on the vehicle that prevent the TPMS (tire pressure warning
system) from functioning properly. Always check the TPMS (tire pres-
sure warning system) malfunction te lltale after replacing one or more
tires or wheels on your vehicle to ensure that the replacement or alter-
nate tires and wheels allow the TPMS (tire pressure warning system) to
continue to function properly.
NOTICE
■Precaution when installing a different tire
When a tire of a different specification or maker is installed, the tire pres-
sure warning system may not operate properly.