TOYOTA PRIUS 2010 3.G Owners Manual

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5-2. Steps to take in an emergency
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*1: Open door warning buzzer:
The open door warning buzzer sounds to alert one or more of the doors is
not fully closed (with the vehicle hav
ing reached a speed of 3 mph [5 km/h]).
*2: 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.
■If the malfunction indicator lamp comes on while driving
First check whether the fuel tank cap is 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.
■ Electric power steering warning light
When the voltage is low or drops, the electric power steering warning light
may come on.

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■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
■ Open moon roof reminder buzzer
The buzzer indicates that the moon roof is not fully closed with the hybrid
system off and the driver’s door opened.

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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
detection sensor may cause the warning light to flash, even if a passen-
ger is not sitting in the seat.
● If a cushion is placed on the seat, the sensor may not detect a passen-
ger, and the warning light may not operate properly.
■
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.

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■If the tire pressure warning system is inoperative
The tire pressure warning system will be disabled in the following condi-
tions:
(When the condition becomes 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.
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.

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■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.
■ Customization that can be co nfigured at Toyota dealer
The vehicle speed linked seat belt reminder buzzer can be disabled. 
(Customizable features P. 587)
However, Toyota recommends that the seat belt reminder buzzer be opera-
tional to alert the driver and front passenger that the seat belts are not fas-
tened.
CAUTION
■ When the electric 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
inflation pressure immediately.
●If the tire pressure warning light comes on even after tire inflation pres-
sure adjustment, it is pr obable 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.

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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 th e vehicle placard or tire inflation
pressure label [tire and load informa tion label], you should determine the
proper tire inflation pr essure for those tires.)
As an added safety feature, your v ehicle has been equipped with a tire
pressure monitoring system (TPMS-tire 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 ti re pressure telltale (tire
pressure warning light).

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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 detec ts 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 prev ent the TPMS (tire pressure warning
system) from functioning properly. Always check the TPMS (tire pres-
sure warning system) malfunction tellt ale 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.

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If a warning message is displayed
If a warning is shown on the multi-information display, stay calm and
perform the following actions:
Master warning light
Multi-information display
The master warning light also
comes on or flashes in order to
indicate that a message is cur-
rently being displayed on the
multi-information display.
If any of the warning light turns on again after performing the fol-
lowing actions, contact your Toyota dealer.
ITO52P158

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Stop the vehicle immediately.
A buzzer sounds and a warning message is shown on the multi-infor-
mation display. The following warnin gs indicate the possibility of dam-
age to the vehicle that may lead to an accident. Immediately stop the
vehicle in a safe place and contact your Toyota dealer.
Warning messageDetails
Indicates an abnormal engine oil pressure. The warning light may turn on if the engine oil pres-
sure is too low.
Indicates a malfunction in the hybrid system.

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Have the vehicle inspected immediately.Failure to investigate the cause of the following warnings may lead to
the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by your Toyota dealer immediately.
Warning messageDetails
(If equipped) Indicates a malfunction in the LED headlight system.
Indicates a malfunction in the parking lock system.
(Flashing)
(If equipped) Indicates a malfunction in the pre-collision system.
A buzzer also sounds.