2012 TOYOTA PRIUS engine braking

31
1-1. Hybrid system
1
Before driving
■
When stopped/during start off
The gasoline engine stops
* when the vehicle is stopped. During
start off, the electric motor (tra ction motor) drives the vehicle. At
slow speeds or when traveling down a gentle slope, the engine
is stopped
* and the electric motor (traction motor) is used.
When shift position is in N, the hybrid battery (traction battery)
will not be charged. Thus, shift to P when the vehicle is stopped.
In addition, when driving in heavy traffic, use D or B.
*: However, when the hybrid battery (traction battery) need to be charged or while the engine is being warmed up, the gasoline
engine may not stop automatically. ( P. 33)
■ During normal driving
The gasoline engine is predominantly used. The electric motor
(traction motor) charges the hybr id battery (traction battery) as
necessary.
■ When accelerating sharply
When the accelerator pedal is depressed heavily, the power of
the hybrid battery (traction battery ) is added to that of the gaso-
line engine via the electric motor (traction motor).
■ When braking (regenerative braking)
The electric motor (traction mo tor) charges the hybrid battery
(traction battery).

32 1-1. Hybrid system
Vehicle proximity notification system
When driving with the gasoline engine stopped, a sound, which
changes in accordance with the dr iving speed, will be played in order
to warn people nearby of the vehicle’s approach. The sound will stop
when the vehicle speed exceeds a pproximately 15 mph (25 km/h).
■Regenerative braking
In the following situations, kinetic energy is converted to electric energy and
deceleration force can be obtained in conjunction with the recharging of the
hybrid battery (traction battery).
●The accelerator pedal is released while driving with the shift position in D
or B.
● The brake pedal is depressed while driving with the shift position in D or
B.
■ Hybrid System Indicator
Hybrid System Indicator represents the
hybrid system power output and regener-
ative charging. (
P. 225)

34 1-1. Hybrid system
■Sounds and vibrations specific to a hybrid vehicle
There may be no engine sounds or vibration even though the vehicle is able
to move. For safety, apply the parking brake and make sure to shift the shift
position to P when parked.
The following sounds or vibrations may occur when the hybrid system is
operating and are not a malfunction:
●The brake system operation sound heard from the front of the vehicle
when the driver’s door is opened.
● Motor sounds may be heard from the engine compartment.
● Sounds may be heard from the hybrid battery (traction battery) when the
hybrid system starts or stops.
● Sounds may be heard from the transmission when the gasoline engine
starts or stops, when driving at low speeds, or during idling.
● Engine sounds may be heard when accelerating sharply.
● Sounds may be heard due to regenerative braking when the brake pedal
is depressed and accelerator is loosened.
● Other sounds, such as motors and mechanical noises, may be heard
from the brake system when the brake pedal is depressed.
● Vibration may be felt when the gasoline engine starts or stops.
● Cooling fan sounds may be heard from the air intake vent. (
P. 37)
● The operation sound of the air conditioning system (air conditioning com-
pressor, blower motor).

54 1-1. Hybrid system
Eco savings record display
By setting the comparison consumption and the gasoline value
beforehand (P. 231), the difference is calculated when the actual
consumption is less than the comparison consumption, and the
amount of money saved is displayed
*1.
If the comparison consumption is set to 0, the consumption cost is
displayed
*1.
*1: The displayed amount is intended only as a guide and may differ from the actual amount.
Savings or consumption costs
for the previous 6 months
EV indicator
*2
Eco Driving Indicator Light*2
Driving distance for each
month
*2: P. 225
■ Remaining hybrid battery (traction battery) charge display
The charge amount of the hybrid battery (traction battery) is automatically
controlled by the hybrid system. For this reason, even if electricity is recov-
ered via the regenerative braking, or electricity is generated via the gasoline
engine, the displayed hybrid battery (traction battery) charge amount may
not reach the highest level (level 8). However, this does not indicate a mal-
function.

184 2-1. Driving procedures
CAUTION
●If the smell of exhaust is noticed inside the vehicle, open the windows and
check that the back door is closed. Large amounts of exhaust in the vehi-
cle can cause driver drowsiness and an accident, resulting in death or a
serious health hazard. Have the vehicle inspected by your Toyota dealer
immediately.
● Do not shift the shift position to P while the vehicle is moving.
Doing so can damage the transmission and may result in a loss of vehicle\
control.
● Do not shift the shift position to R while the vehicle is moving forward.
Doing so can damage the transmission and may result in a loss of vehicle\
control.
● Do not shift the shift position to D while the vehicle is moving backward.
Doing so can damage the transmission and may result in a loss of vehicle\
control.
● Moving the shift position to N while the vehicle is moving will disengage
the hybrid system. Engine braking is not available with the hybrid system
disengaged.
● During normal driving, do not turn off the hybrid system. Turning the hybrid
system off while driving will not cause loss of steering or braking control,
but the power assist to these systems will be lost. This will make it more
difficult to steer and brake, so you should pull over and stop the vehicle as
soon as it is safe to do so.
However, in the event of an emergency, such as if it becomes impossible
to stop the vehicle in the normal way: P. 556
● Use engine braking (shift position B instead of shift position D) to maintain
a safe speed when driving down a steep hill.
Using the brakes continuously may cause the brakes to overheat and lose
effectiveness. ( P. 202)

185
2-1. Driving procedures
2
When driving
CAUTION
●
Do not adjust the positions of the steering wheel, the seat, or the inside or
outside rear view mirrors while driving.
Doing so may result in a loss of vehicle control that can cause accidents,
resulting in death or serious injury.
● Always check that all passengers’ arms, heads or other parts of their body
are not outside the vehicle, as this may result in death or serious injury.
● Do not drive in excess of the speed limit. Even if the legal speed limit per-
mits it, do not drive over 85 mph (140 km/h) unless your vehicle has high-
speed capability tires. Driving over 85 mph (140 km/h) may result in tire
failure, loss of control and possible injury. Be sure to consult a tire dealer
to determine whether the tires on your vehicle are high-speed capability
tires or not before driving at such speeds.
■ When driving on slippery road surfaces
●Sudden braking, acceleration and steering may cause tire slippage and
reduce your ability to control the vehicle, resulting in an accident.
● Sudden acceleration, engine braking due to shift changing, or changes in
engine speed could cause the vehicle to skid, resulting in an accident.
● After driving through a puddle, depress the brake pedal to make sure that
the brakes are functioning properly. Wet brake pads may prevent the
brakes from functioning properly. If the brakes on only one side are wet
and not functioning properly, steering control may be affected, resulting in
an accident.

203
2-1. Driving procedures
2
When driving
Shift position indicator
The position of the frame on the shift position indicator changes in
accordance with the current shift position.
When any shift position other than D or B is selected, the arrow toward
B and B position indicator disappear from the shift position indicator.
When selecting the shift position, make sure that the shift position has
been changed to the desired position by checking the shift position indica-
tor provided on the instrument cluster.
■ Shift position purpose
*: For good fuel economy and noise reduction, the D position should usu-
ally be used.
Shift positionFunction
PParking the vehicle/starting the hybrid system
RReversing
NNeutral
DNormal driving*
BApplying moderate engine braking when driving down hills or on steep slopes

208 2-1. Driving procedures
■About engine braking
When shift position B is selected, releasing the accelerator pedal will apply
engine braking.
●When the vehicle is driven at high speeds, compared to ordinary gaso-
line-fueled vehicles, the engine braking deceleration is felt less than that
of other vehicles.
● The vehicle can be accelerated even when shift position B is selected.
If the vehicle is driven continuously in the B position, fuel efficiency will
become low. Usually, shift the shift position to D.
■ When driving with cruise control or radar cruise control activated
Even if switching the driving mode to power mode with the intent of enabling
engine braking, engine braking will not activate because cruise control or
radar cruise control will not be canceled.
■ When canceling Eco drive mode/power mode
●Press the switch again. Also, power mode will be canceled automatically
when the “POWER” switch is turned off. However, Eco drive mode will
not be canceled automatically until the switch is pressed, even if the
“POWER” switch is turned off.
● When in Eco drive mode, if the power mode switch is pressed or the
operation is reversed, the mode will switch to that of the last switch to be
pressed.
■ Switching the drive mode when in EV drive mode
P. 201
■ After recharging/reconnecting the 12-volt battery
P. 433