2010 TOYOTA PRIUS engine

522 5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection procedure
Once 
(Flashing)The elec-
tronic key
does not
operate
properly.
P. 542
 Power
was
turned off
due to
the auto-
matic
power off
function.Next time when
starting the
hybrid system,
increase the
engine speed
slightly and
maintain that
level for approxi-
mately 5 min-
utes to recharge
the battery.
■ Changing the engine oil
Make sure to reset oil change system.

5
When trouble arises
523
5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
NOTICE
■
While the engine oil level warning is displayed
Continued engine operation with low engine oil will damage the engine.
■ Engine oil maintenance message
The warning message is based on the projected driving range after engine
oil maintenance message is reset. 
The system does not monitor the purity of the engine oil.

5
When trouble arises
545
5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
■
Starting the hybrid system when the 12 volt battery is discharged
The hybrid system cannot be started by push-starting. In addition, the shift
position may not changed from “P”.
■ 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.
■ When the 12 volt battery is removed or discharged
The hybrid system may not start. (
P. 438)
Start the engine of the second vehicle. Increase the engine
speed slightly and maintain at that level for approximately 5
minutes to recharge the 12 volt battery of your vehicle.
Turn the “POWER” switch to ACCESSORY mode.
Maintain the engine speed on the second vehicle and turn
the “POWER” switch to ON mode, then start your vehicle’s
hybrid system.
Make sure the “READY” indicator comes on. If the indicator
does not come on, contact your Toyota dealer.
Once the vehicle’s hybrid syst em has started, remove the
jumper cables in the exact reverse order in which they were
connected.
Once the hybrid system starts, ha ve the vehicle checked at your
Toyota dealer as soon as possible.STEP4
STEP5
STEP6
STEP7
STEP8

548
5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
If your vehicle overheats
Correction procedures■ If the high coolant temperatur e warning light comes on or
flashes
Stop the vehicle in a safe place and turn off the air condition-
ing system.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the hybrid system. Carefully lift the hood after the
steam subsides and then restart the hybrid system.
If you do not see steam: 
Leave the hybrid system operating and carefully lift the
hood.
The following may indicate that your vehicle is overheating:
● The high coolant temperature warn ing light comes on or flashes:
The engine may be overheating.
● “HYBRID SYSTEM OVERHEAT” is shown on the multi-informa-
tion display: 
The power control unit may be overheating.
Follow the correction procedure as described below.
STEP1
STEP2

5
When trouble arises
549
5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
Check to see if the cooling fans are operating.
If the fans are operating: 
Wait until the high coolant temperature warning light goes
off and then stop the hybrid system.
If the fans are not operating:  Stop the hybrid system immedi ately and call your local
Toyota dealer.
After the hybrid system has
cooled down sufficiently, check
the engine coolant level and
inspect the radiator core (radia-
tor) for any leaks.
If necessary, add engine coolant
up to the “FULL” line.
Water can be used in an emer-
gency measure if engine coolant
is unavailable. (P. 562)
STEP3
STEP4
ITO52P130
STEP5

552 5-2. Steps to take in an emergency
PRIUS_U (OM47668U) U.S.A.
CAUTION
■To prevent an accident or injury when inspecting under the hood of
your vehicle
● If steam is seen coming from under the hood, do not open the hood until
the steam has subsided. The engine compartment may be very hot, caus-
ing serious injury such as burns.
● With a hybrid vehicle, there are times when the gasoline engine automati-
cally starts to run or the cooling fans suddenly start to operate. Do not
touch or approach the rotating parts of the belt or fans. Doing so may lead
to fingers, clothes or tools getting caught, resulting in an accidental injury.
● Do not loosen the coolant reservoir cap while the hybrid system and radia-
tor are hot. 
Serious injury, such as burns, may result from hot coolant and steam
released under pressure.
NOTICE
■ When adding engine/power control unit coolant
Wait until the hybrid system has cooled down before adding engine/power
control unit coolant. 
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid sys-
tem too quickly can cause damage to the hybrid system.

558 6-1. Specifications
PRIUS_U (OM47668U) U.S.A.■
Engine number and electric mo tor (traction motor) number
The gasoline engine number and
electric motor (traction motor)
number are stamped as shown.
Gasoline engine number
Electric motor (traction motor)
number
Engine
Fuel
Model2ZR-FXE
Type 4-cylinder in line, 4-cycle, gasoline
Bore and stroke 3.17  3.48 in. (80.5  88.3 mm)
Displacement109.7 cu. in. (1798 cm3)
Valve clearance
(engine cold) Automatic adjustment
Fuel typeUnleaded gasoline only
Octane Rating
87 (Research Octane Number 91) or higher
Fuel tank capacity 11.9 gal. (45 L, 9.9 Imp.gal.)

560 6-1. Specifications
PRIUS_U (OM47668U) U.S.A.
Lubrication system■ Engine oil selection
“Toyota Genuine Motor Oil” is used in your Toyota vehicle. Use
Toyota approved “Toyota Genuine Motor Oil” or equivalent to sat-
isfy the following grade and viscosity.
Oil grade: ILSAC multigrade engine oil
Recommended viscosity: SAE 0W-20
SAE 0W-20 is the best choice for
good fuel economy and good
starting in cold weather.
If SAE 0W-20 is not available,
SAE 5W-20 may be used. How-
ever, it must be replaced with
SAE 0W-20 at the next oil
change.
The 0W portion of the oil viscosity rating indicates the characteristic of the
oil which allows cold startability. Oils with a lower value before the W allow
for easier starting of the engine in cold weather.
The 20 in 0W-20 indicates the oil viscosity when the oil is at its operating
temperature. An oil with a higher viscosity may be better suited if the vehi-
cle is operated at high speeds, or under extreme load conditions.
Oil capacity 
Drain and refill 
(reference) With filter
Without filter
4.4 qt. (4.2 L, 3.7 Imp.qt.)
4.1 qt. (3.9 L, 3.4 Imp.qt.)
Outside temperature