TOYOTA PRIUS PLUG-IN HYBRID 2021 Owners Manual

4615-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
5
Driving
When your vehicle is too close to
a vehicle ahead, and sufficient
automatic deceleration via the
cruise control is not possible, the
display will flash and the buzzer
will sound to alert the driver. An
example of this would be if
another driver cuts in front of you
while you are following a vehicle.
Depress the brake pedal to
ensure an appropriate vehicle-to-
vehicle distance.
■Warnings may not occur when
In the following instances, warnings may not occur even when the
vehicle-to-vehicle distance is small.
●When the speed of the preceding vehicle matches or exceeds
your vehicle speed
●When the preceding vehicle is traveling at an extremely slow
speed
●Immediately after the cruise control speed was set
●When depressing the accelerator pedal
Approach warning (vehicle-to-vehicle distance control mode)

4625-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
When constant speed control mode is selected, your vehicle will main-
tain a set speed without controlling the vehicle-to-vehicle distance.
Select this mode only when vehicle-to-vehicle distance control mode
does not function correctly due to a dirty radar, etc.
With the cruise control off,
press and hold the “ON-OFF”
button for 1.5 seconds or more.
Immediately after the “ON-OFF”
button is pressed, the dynamic
radar cruise control indicator will
come on. Afterwards, it switches to
the cruise control indicator.
Switching to constant speed con-
trol mode is only possible when
operating the lever with the cruise
control off.
Accelerate or decelerate, with
accelerator pedal operation, to
the desired vehicle speed (at or
above approximately 30 km/h
[20 mph]) and push the lever
down to set the speed.
Cruise control “SET” indicator will
come on.
The vehicle speed at the moment
the lever is released becomes the
set speed.
Adjusting the speed setting: P. 458
Canceling and resuming the speed setting: P. 460
Selecting constant speed control mode
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4635-5. Using the driving support systems
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Driving
When this function is enabled and the system is operating in vehicle-
to-vehicle distance control mode (P. 455), when a speed limit sign is
detected, the recognized speed limit will be displayed with an up/
down arrow. The set speed can be increased/reduced to the recog-
nized speed limit by pushing the lever up or down.
●When the current set speed is
lower than the recognized
speed limit
Push the lever up.
●When the current set speed is
higher than the recognized
speed limit
Push the lever down.
Dynamic Radar Cruise Control with Road Sign Assist can be enabled/
disabled in on the multi-information display. (P. 230)
When the Dynamic Radar Cruise Control with Road Sign Assist is
operating, while driving down a hill, the vehicle speed may exceed the
set speed.
In this case, the displayed set vehicle speed will be highlighted and a
buzzer will sound to alert the driver.
Dynamic Radar Cruise Control with Road Sign Assist
Enabling/Disabling the Dynamic Radar Cruise Control with Road
Sign Assist

4645-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47D72E_(EE)
■Dynamic radar cruise control with full-speed range can be set when
●The shift position is in D.
●The desired set speed can be set when the vehicle speed is approximately
30 km/h (20 mph) or more.
(However, when the vehicle speed is set while driving at below approxi-
mately 30 km/h [20 mph], the set speed will be set to approximately 30 km/h
[20 mph].)
■Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After acceler-
ating, the set speed resumes. However, during vehicle-to-vehicle distance
control mode, the vehicle speed may decrease below the set speed in order
to maintain the distance to the preceding vehicle.
■When the vehicle stops while follow-up cruising
●Pushing the lever up while the vehicle ahead stops will resume follow-up
cruising if the vehicle ahead starts off within approximately 3 seconds after
the lever is pushed up.
●If the vehicle ahead starts off within 3 seconds after your vehicle stops, fol-
low-up cruising will be resumed.
■Automatic cancelation of vehicle-to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically canceled in the fol-
lowing situations.
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off.
●The sensor cannot detect correctly because it is covered in some way.
●Pre-collision braking is activated.
●The parking brake is operated.
●The vehicle is stopped by system control on a steep incline.
●The following are detected when the vehicle has been stopped by system
control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.
In this situation, the shift position may automatically switch to P. (P. 382)
If vehicle-to-vehicle distance 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.

4655-5. Using the driving support systems
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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)

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

4675-5. Using the driving support systems
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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

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

4695-5. Using the driving support systems
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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.
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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