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4655-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatically canceled in the following situa-
tions:
●Actual vehicle speed is more than approximately 16 km/h (10 mph) below
the set vehicle speed.
●Actual vehicle speed falls below approximately 30 km/h (20 mph).
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off.
●Pre-collision braking is activated.
If constant speed control mode is automatically canceled for any reasons
other than the above, there may be a malfunction in the system. Contact any
authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
■The Dynamic Radar Cruise Control with Road Sign Assist may not oper-
ate properly when
As the Dynamic Radar Cruise Control with Road Sign Assist may not oper-
ate properly in conditions in which RSA may not operate or detect correctly
(P. 449), when using this function, make sure to check the speed limit
sign displayed.
In the following situations, the set speed may not be changed to the recog-
nized speed limit by pushing the lever up or down.
●If speed limit information is not available
●When the recognized speed limit is the same as the set speed
●When the recognized speed limit is outside of the speed range that the
dynamic radar cruise control system can operate
■Brake operation
A brake operation sound may be heard and the brake pedal response may
change, but these are not malfunctions.
■Warning messages and buzzers for dynamic radar cruise control with
full-speed range
Warning messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. If a warning message
is shown on the multi-information display, read the message and follow the
instructions. (P. 416, 723)
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4665-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the
brake pedal when deceleration of the system is insufficient or operate the
accelerator pedal when acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning (P. 461) may not be activated.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same lane
●Vehicles with small rear ends (trailers with no load on board, etc.)
●Motorcycles traveling in the same lane
●When water or snow thrown up by the surrounding vehicles hinders the
detecting of the sensor
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
●Preceding vehicle has an extremely high
ground clearance
Page 467 of 816
4675-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
■Conditions under which the vehicle-to-vehicle distance control mode
may not function correctly
In the case of the following conditions, operate the brake pedal (or accelera-
tor pedal, depending on the situation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system
may not operate properly.
●When the vehicle ahead of you decelerates suddenly
●When driving on a road surrounded by a structure, such as in a tunnel or on
a bridge
●While the vehicle speed is decreasing to the set speed after the vehicle
accelerates by depressing the accelerator pedal ●When the road curves or when the lanes
are narrow
●When steering wheel operation or your
position in the lane is unstable
Page 468 of 816
4685-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
Driving mode select switch
Repeatedly press the switch until the system changes to the intended
driving mode.
Each time the switch is pressed, the driving mode changes in the following
order and the “ECO MODE” and “PWR MODE” indicators turn on or off
accordingly.
In response to driving conditions, one of 3 driving modes can be
selected.
Driving modes
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4695-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
Normal mode
Suitable for normal driving.
When normal mode is selected, the “ECO MODE” and “PWR MODE”
indicators turn off.
Power mode
Suitable for when crisp handling and enhanced accelerator
response are desired, such as when driving on mountainous roads.
When power mode is selected, the “PWR MODE” indicator will illumi-
nate on the main display.
Eco drive mode
Suitable for driving that improves fuel economy by generating
torque in response to accelerator pedal operations more smoothly
than in normal mode.
When Eco drive mode is selected, the “ECO MODE” indicator will illumi-
nate on the main display.
While the air conditioning is being used, the fan speed setting mode will
be changed to “ECO” mode automatically (P. 576), allowing for driving
that leads to even better fuel economy.
■Automatic deactivation of power mode
●Power mode will be canceled and changed to normal mode automatically
when the power switch is turned off.
●However, normal mode and eco drive mode will not be canceled automati-
cally until the switch is pressed, even if the power switch is turned off.
1
2
3
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4705-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
Speed limiter
Press the switch to activate the
speed limiter.
Press the switch once more to
deactivate the speed limiter.
Accelerate or decelerate to the
desired speed and push the lever
down to set the desired maximum
speed.
If the lever is pushed down while
the vehicle is stopped or being
driven of 30 km/h (19 mph) or less,
the set speed will be 30 km/h
(19 mph).
A desired maximum speed can be set using the cruise control
switch.
The speed limiter prevents vehicle speed from exceeding the set
speed.
Setting the vehicle speed
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4715-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is obtained.
Fine adjustment of the set speed
can be made by lightly pushing the
lever up or down and releasing it.
Cancel
Pull the lever towards you to can-
cel the speed limiter.
Resume
To resume use of the speed limiter,
push the lever up.
■Exceeding the set speed
In the following situations, the vehicle speed exceeds the set speed, and
main display will be highlighted:
Adjusting the speed setting
1
2
Canceling and resuming the speed limiter
1
2
●When fully depressing the accelerator
pedal
●When driving down a hill (a buzzer also
sounds)
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4725-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Automatic speed limiter cancellation
The set speed is automatically canceled in any of the situations:
● Cruise control is activated.
● When the VSC system and/or TRC system is turned off by pressing the
VSC OFF switch.
■ If the “Check Speed Limiter System” is displayed on the multi-informa-
tion display
Stop in a safe location, turn the power switch off and back on again, and then
set the speed limiter. If the speed limiter cannot be set, the system may be
malfunctioning. Even though the vehicle can be driven normally, have the
vehicle inspected by any authorized Toyota retailer or Toyota authorized
repairer, or any reliable repairer.
WARNING
■ To avoid operating the speed limiter by mistake
Keep the speed limiter switch off when not in use.
■ Situations unsuitable for speed limiter
Do not use the speed limiter in either of the following situations.
Doing so may result in control of the vehicle being lost and could cause a
serious or fatal accident.
● On slippery roads, such as those covered with rain, ice or snow
● On steep hills
NOTICE
When a warning is issued using the meter display and buzzer after exceed-
ing the set speed limit on a steep decline, depress the brake pedal to decel-
erate.