engine TOYOTA PRIUS 2008 2.G Service Manual

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When trouble arises
423
5-1. Essential information
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If you think something is wrong
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Toyota dealer as soon as
possible.
■ Visible symptoms
●Fluid leaks under the vehicle
(Water dripping from the air cond itioning after use is normal.)
● Flat-looking tires or uneven tire wear
● Engine coolant temperature displa y indicates that the temper-
ature is higher than normal. ( P. 146)
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the hybrid system
■ Operational symptoms
●Engine missing, stumbling or running rough
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one side when driving on a level road
● Loss of brake effectiveness, s pongy feeling, pedal almost
touches the floor

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5-1. Essential information
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Event data recorder
In a crash or a near car crash eventThe SRS airbag sensor assembly contains the EDR. In a crash or a
near car crash event, this device may record some or all of the follow-
ing information:
● Gasoline engine speed
● Whether the brake pedal was applied or not
● Vehicle speed
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver’s seat position
● SRS airbag deployment data
● SRS airbag system diagnostic data
● Front passenger’s occupant classification
The information above is intended to be used for the purpose of
improving vehicle safety performan ce. Unlike general data recorders,
the EDR does not record sound data such as conversation between
passengers.
Your vehicle has computers that monitor and control certain aspects
of your vehicle. These computers assi st in driving and maintaining
optimal vehicle performance.
Besides storing data useful for tr oubleshooting, there is a system to
record data in a crash or a near car crash event. This is called an
Event Data Recorder (EDR).

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When trouble arises
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5-2. Steps to take in an emergency
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Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehi-
cle that may lead to an accident. Immediately stop the vehicle in a
safe place and contact your Toyota dealer.
Have the vehicle inspected by your Toyota dealer immediately.Failing 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 lightWarning light/Details
Charging system warning light Indicates a malfunction in the vehicle’s charging system.
Low engine oil pressure warning light Indicates that the engine oil pressure is too low.

*1Hybrid system warning light Indicates a malfunction in the hybrid system.
Warning lightWarning light/Details
Malfunction indicator lamp Malfunction in:
• The electronic hybrid system control system;
• The electronic throttle control system; or
• The transmission control system.
SRS warning light Malfunction in:
• The SRS airbag system;
• Front passenger occupant classification system; or
• The seat belt pretensioner system.

430 5-2. Steps to take in an emergency
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*1:This warning light is displayed 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.
High coolant temperature
warning light Indicates high engine cool-
ant temperature P. 456
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 multi-
information display.
Warning lightWarning light/DetailsCorrection procedure

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5-2. Steps to take in an emergency
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If you have a flat tire
Remove the flat tire and replace it with the spare provided.
■Before jacking up the vehicle
●Stop the vehicle on a hard, flat surface.
● Set the parking brake.
● Push the “P” position switch
● Stop the engine.
● Turn on the emergency flashers.
■ Location of the spare tire, jack and tools
ITY52P001
Wheel nut
wrench
Jack handle
Jack
Towing eyelet
Spare tire

448
5-2. Steps to take in an emergency
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If the hybrid system will not start
If the engine will not start even though correct starting procedures
are being followed (
P. 130), consider each of the following points.
■ The hybrid system will not start even when the starter motor
operates normally.
One of the following may be the cause of the problem.
●The electronic key battery may be discharged. ( P. 450)
● The engine may be flooded.
Try to restart the hybrid system once more following correct
starting procedures. (P. 130)
● There may be a malfunction in the immobilizer system.
( P. 8 1 )
■ The interior lights and headlight s are dim, or the horn does
not sound or sounds at a low volume
One of the following may be the cause of the problem.
● The 12 volt battery may be discharged. ( P. 451)
● The 12 volt battery terminal c onnections may be loose or cor-
roded.
■ The interior lights and headlights do not turn on, or the horn
does not sound
One of the following may be the cause of the problem.
●One or both of the 12 volt battery terminals may be discon-
nected.
● The 12 volt battery may be discharged. ( P. 451)
Contact your Toyota dealer if the problem cannot be repaired,
or if repair procedures are unknown.

450
5-2. Steps to take in an emergency
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If the electronic key does not operate properly
Locking and unlocking the doorsUsing the mechanical key in
order to perform the following
operations:Locks all doors
Unlocks the door
Turning the key rearward unlocks
the driver’s door. Turning the key
once again unlocks the other
doors.
Starting the hybrid system
To start the hybrid system, insert
the key into the key slot.
( P. 132)
If the electronic key 12 volt batter y is discharged, the doors can be
opened by the mechanical key. The engine system can be still
started by following the procedure.
21
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■ Replacing the key battery
As this procedure is the temporary measure, it is recommended that the
electronic key battery be replaced immediately. ( P. 396)

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When trouble arises
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5-2. Steps to take in an emergency
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If the vehicle 12 volt batter y is discharged
The following procedures may be used to start the engine if the vehi-
cle’s 12 volt battery is discharged.
You can call your Toyota dealer, or qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehi-
cle with a 12 volt battery, you can jump start your Toyota following
the steps below.
Open the hood and fuse block cover.
Open the exclusive jump start-
ing terminal cover.
STEP1
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STEP2

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When trouble arises
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5-2. Steps to take in an emergency
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■
Starting the hybrid system when the battery is discharged
The hybrid system cannot be started by push-starting.
■ Avoiding a discharged 12 volt battery
● Turn off the headlights and the audio system while the hybrid system is
turned off.
● Turn off any unnecessary electrical components when the vehicle is run-
ning at a low speed for an extended period, such as in heavy traffic, etc.
Start the engine of the second vehicle. Increase the engine
speed slightly and maintain at that level for approximately
five minutes to recharge the 12 volt battery of your vehicle.
Open and close any of the doors with the “POWER” switch
OFF.
Maintain the engine speed on the second vehicle and turn
the “POWER” switch to the ON mode, then start the vehi-
cle’s engine.
Make sure the “READY” light comes on. If the “READY”
light will not come on and the hybrid system will not start
after you recharge the battery, do the following procedure.
Turn the hybrid system off. Open and close the driver’s
door. Then push the “POWER” switch briefly and firmly. If
the light does not come on, contact your Toyota dealer.
Once the vehicle’s engine has started, remove the jumper
cables in the exact reverse order in which they were con-
nected.
Once the engine starts, have the vehicle checked at your Toyota
dealer as soon as possible.STEP4
STEP5
STEP6
STEP7
STEP8

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5-2. Steps to take in an emergency
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If your vehicle overheats
Correction proceduresStop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine and carefully lift the hood.
If you do not see steam: Leave the engine running and carefully lift the hood.
Remove the engine compartment cover. ( P. 365)
Check to see if the cooling fan is operating.
If the fan is operating: Wait until the engine coolant temperature gauge begins to
fall and then stop the engine.
If the fan is not operating: Stop the hybrid system immediately and call your local Toy-
ota dealer.
After the hybrid system has
cooled down sufficiently, check
the coolant level and inspect the
radiator core (radiator) for any
leaks.
The following may indicate that your vehicle is overheating:
The high engine coolant temperature warning light comes on:
The engine may be overheating.
Follow the correction procedure as described blow.
STEP1
STEP2
STEP3
STEP4
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STEP5