Page 341 of 818

3395-3. Operating the lights and wipers
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
■Automatic light off system
● When the light switch is in the or position: The headlights turn
off automatically if the power switch is turned to ACCESSORY mode or
turned off.
● When the light switch is in the position: The headlights and all lights
turn off automatically if the power switch is turned to ACCESSORY mode or
turned off.
To turn the lights on again, turn the power switch to ON mode, or turn the light
switch to the position once and then back to the or posi-
tion.
■ Automatic headlight leveling system
The level of the headlights is automatically adjusted according to the number
of passengers and the loading condition of the vehicle to ensure that the
headlights do not interfere with other road users.
■ Light reminder buzzer
A buzzer sounds when the power switch is turned off and the driver’s door is
opened while the lights are turned on.
■ 12-volt battery-saving function
In order to prevent the vehicle 12-volt battery from discharging, if the light
switch is in the position when the power switch turned off the 12-volt
battery saving function will operate and automatically turn off all the lights
after approximately 20 minutes.
When any of the following are performed, the 12-volt battery-saving function
is canceled once and then reactivated. All the lights will turn off automatically
20 minutes after the 12-volt battery-saving function has been reactivated:
● When the headlight switch is operated
● When a door is opened or closed
■ If “Headlight System Malfunction Visit Your Dealer” is displayed on the
multi-information display
The system may be malfunctioning. Have the vehicle inspected by any autho-
rized Toyota retailer or Toyota authorized repairer, or any reliable repairer.
■ Customization
Settings (e.g. light sensor sensitivity) can be changed.
(Customizable features: P. 726)
Page 348 of 818
3465-3. Operating the lights and wipers
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
■If “Headlight System Malfunction Visit Your Dealer” is displayed on the
multi-information display
The system may be malfunctioning. Have the vehicle inspected by any autho-
rized Toyota retailer or Toyota authorized repairer, or any reliable repairer.
■Customization
Some functions can be customized. (Customizable features: P. 726)
Page 368 of 818

3665-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
■If a warning message is displayed on the multi-information display
A system may be temporarily unavailable or there may be a malfunction in
the system.
●In the following situations, perform the actions specified in the table. When
the normal operating conditions are detected, the message will disappear
and the system will become operational.
If the message does not disappear, contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
SituationActions
When the area around a cam-
era is covered with dirt, mois-
ture (fogged up, covered with
condensation, ice, etc.), or
other foreign matter
Using the wiper and A/C function,
remove the dirt and other attached mat-
ter. (P. 527)
When the temperature around
the front camera is outside of
the operational range, such as
when the vehicle is in the sun or
in an extremely cold environ-
ment
If the front camera is hot, such as after
the vehicle had been parked in the sun,
use the air conditioning system to
decrease the temperature around the
front camera.
If a sunshade was used when the vehi-
cle was parked, depending on its type,
the sunlight reflected from the surface
of the sunshade may cause the tem-
perature of the front camera to become
excessively high.
If the front camera is cold, such after the
vehicle is parked in an extremely cold
environment, use the air conditioning
system to increase the temperature
around the front camera.
The area in front of the front
camera is obstructed, such as
when the hood is open or a
sticker is attached to the part of
the windshield in front of the
front camera.
Close the hood, remove the sticker, etc.
to clear the obstruction.
When “Pre-Collision System
Unavailable” is displayed.Check whether there is attached materi-
als on the radar sensor and radar sensor
cover, and if there is, remove it.
Page 369 of 818

3675-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
●In the following situations, if the situation has changed (or the vehicle has
been driven for some time) and the normal operating conditions are
detected, the message will disappear and the system will become opera-
tional.
If the message does not disappear, contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable repairer.
• When the temperature around the radar sensor is outside of the opera-
tional range, such as when the vehicle is in the sun or in an extremely
cold environment
• When the front camera cannot detect objects in front of the vehicle, such
as when driving in the dark, snow, or fog, or when bright lights are shining
into the front camera
• Depending on the conditions in the vicinity of the vehicle, the radar may
judge the surrounding environment can not be properly recognized. In
that case, “Pre-Collision System Unavailable” is displayed.
Page 371 of 818
3695-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
■Pre-collision warning
When the system determines
that the possibility of a frontal
collision is high, a buzzer will
sound and a warning message
will be displayed on the multi-
information display to urge the
driver to take evasive action.
■Pre-collision brake assist
When the system determines that the possibility of a frontal colli-
sion is high, the system applies greater braking force in relation to
how strongly the brake pedal is depressed.
■Pre-collision braking
If the system determines that the possibility of a frontal collision is
extremely high, the brakes are automatically applied to help avoid
the collision or reduce the impact of the collision.
System functions
Page 374 of 818
3725-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
■Enabling/disabling the pre-collision system
The pre-collision system can be enabled/disabled on (P. 247)
of the multi-information display.
The system is automatically enabled each time the power switch is
turned to ON mode.
If the system is disabled, the
PCS warning light will turn on
and a message will be dis-
played on the multi-information
display.
■Changing the pre-collision warning timing
The pre-collision warning timing can be changed on (P. 247)
of the multi-information display.
The warning timing setting is retained when the power switch is turned
off.
However, if the pre-collision system is disabled and re-enabled, the
operation timing will return to the default setting (middle).
Early
Middle
This is the default setting.
Late
Changing settings of the pre-collision system
1
2
3
Page 380 of 818

3785-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the wheels are misaligned
• If a wiper blade is blocking the front camera
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is misaligned
●In some situations such as the following, sufficient braking force may not be
obtained, preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when
the brake parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively
worn, improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery sur-
face
■If VSC is disabled
●If VSC is disabled (P. 511), the pre-collision brake assist and pre-collision
braking functions are also disabled.
●The PCS warning light will turn on and “VSC Turned Off Pre-Collision Brake
System Unavailable” will be displayed on the multi-information display. • If the front of the vehicle is raised or
lowered
Page 383 of 818

3815-5. Using the driving support systems
Prius Plug-in Hybrid_OM_OM47F38E_(EE)
5
Driving
WARNING
■Conditions in which functions may not operate properly
In the following situations, the functions may not operate properly and the
vehicle may depart from its lane. Drive safely by always paying careful
attention to your surroundings and operate the steering wheel to correct the
path of the vehicle without relying solely on the functions.
● When the follow-up cruising display is displayed (P. 389) and the pre-
ceding vehicle is swaying. (Your vehicle may sway accordingly and depart
from the lane.)
● When the follow-up cruising display is displayed (P. 389) and the pre-
ceding vehicle departs from its lane. (Your vehicle may follow the preced-
ing vehicle and depart from the lane.)
● When the follow-up cruising display is displayed (P. 389) and the pre-
ceding vehicle is being driven extremely close to the left/right lane line.
(Your vehicle may follow the preceding vehicle and depart from the lane.)
● Vehicle is being driven around a sharp curve.
●When the follow-up cruising display is
displayed ( P. 389) and the preceding
vehicle changes lanes. (Your vehicle
may follow the preceding vehicle and
also change lanes.)
●Objects or patterns that could be mis-
taken for white (yellow) lines are pres-
ent on the side of the road (guardrails,
reflective poles, etc.).