
PRIUS PRIME_OM_OM47C77U_(U)
4755-5. Using the driving support systems
5
Driving
Assume an ordinary driving
posture, rest your hands
lightly on the steering wheel
without applying any force,
directly confirm the safety of
the area to the front and
around the vehicle and
slowly proceed forward while
adjusting your speed by
depressing the brake pedal.
When this is done, a high-
pitched beep is emitted and
an indicator on the meter illu-
minates at the same time,
after which assist control will
start.
●When the steering wheel auto operation starts, the steering
wheel auto operation display ( P. 459) and assistance level
indicator ( P. 459) will be shown in the display area.
● To stop assist control, press the S-APGS switch.
● When the vehicle speed is too high, a sharp beeping sound is
emitted and assist c ontrol is stopped. (P. 482)
● If the space turns out to be too narrow after assist control
starts, a sharp beeping sound is emitted and assist control is
stopped.
When a beep sounds once and
the stop display ( P. 459) is
shown on the display, stop the
vehicle.
Change the shift position to R.2
3
4

PRIUS PRIME_OM_OM47C77U_(U)
4795-5. Using the driving support systems
5
Driving
When the Simple Advanced Park ing Guidance System cannot be
operated, or when operation is stopped, canceled, etc., the one of the
following message is displayed on the multi-information display . Take
appropriate action acc ording to the display.
■When it is not possible to operate
Multi-information display messages
MessageSituation/Handling method
The system may be malfunctioning.
Turn the power switch off and then start the
hybrid system.
Have the vehicle inspected by your Toyota
dealer if the message is displayed again.
There may be a system failure.
Power steering equipment is temporarily overheat-
ing.
Turn the power switch off, wait for a little
while, and then start the hybrid system again.
The hybrid system is not operating.
Start the hybrid system.
Ice, snow, dirt, etc., has adhered to the sensor.
Remove any ice, snow, dirt, etc.
The sensor is frozen.
Once the sensor thaws, the system will return
to normal.
The 12-volt battery has been removed and rein-
stalled.
Drive the vehicle straight ahead for 5 seconds
or more at a speed of approximately 22 mph
(35 km/h) or higher.
The S-APGS switch is operated when the vehicle
speed exceeds 19 mph (30 km/h).
Operate the switch when the vehicle speed is
approximately 19 mph (30 km/h) or less.
Assist control is started while the steering wheel is
held.
Rest your hands on the steering wheel with-
out applying any force. Assist control will
start.

480
PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
The vehicle is moved and assist control is started
while the steering wheel is held.
Stop the vehicle and follow the guidance pro-
vided by the system to start assist control.
The S-APGS switch is operated when there is not
enough space to the front and rear of the vehicle
when departing from a parallel parking spot.
The vehicle cannot depa rt using assist con-
trol as there is not enough space to the front
and rear of the vehicle . Confirm the safety of
your surroundings before departing.
The S-APGS switch is operated in an area where
there are no obstacles to the front of the vehicle, or
there are obstacles to the sides and the vehicle can-
not depart from the parallel parking spot.
Assist control cannot be used for departure,
as there are obstacles to the sides of the vehi-
cle or departure can easily be performed man-
ually. Confirm the safety of your surroundings
before departing.
The S-APGS switch is operated in an area with no
parking spaces, or operated in an area where the
road width for parking is narrow.
Assist control cannot be used, as there is no
parking space. Proceed to a parking space
which width is approximately 8.5 ft. (2.6 m) or
larger.
Assist control cannot be used, as the road
width is narrow. Proceed to a parking space
where the road width is approximately 15 ft.
(4.5 m) or larger.
The S-APGS switch is operated at a space that is
too narrow for the vehicle to park in.
Assist control cannot be used, as there is no
parking space. Proceed to a parking space
that is approximately 8.5 ft. (2.6 m) or larger.
MessageSituation/Handling method

482
PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
■When the operation is canceled
The maximum number of movements for multi-turn
maneuvering is reached during assist control, or the
target parking spot cannot be reached due to the
control being used on a road with steep grade.
Follow the assist control guidance and use
the system in a wide space that does not have
a steep grade.
MessageSituation/Handling method
MessageSituation/Handling method
The driver holds the
steering wheel during
assist control.
Stop the vehicle and
rest your hands on the
steering wheel without
applying any force.
Then press the S-APGS
switch to restart assist
control.
The vehicle speed
exceeds 4 mph
(7 km/h) during assist
control.
The S-APGS switch
is pressed while
assist control is tem-
porarily stopped and
the steering wheel is
firmly held.
Rest your hands on the
steering wheel without
applying any force.
Then stop the vehicle to
restart assist control.
The S-APGS switch
is pressed while
assist control is tem-
porarily stopped and
the vehicle is moving.
Assist control is tem-
porarily stopped
(able to be restarted)
Stop the vehicle and
rest your hands on the
steering wheel without
applying any force.
Then press the S-APGS
switch to restart assist
control.

488
PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
WARNING
●Observe the following precautions, as the sensors may stop functioning
properly which may lead to an accident.
• Do not subject the sensor to strong shocks by hitting it, etc. The sen-
sors may not function properly.
• When using a high-pressure washer to wash the vehicle, do not spray
water directly on the sensors. Equipment may not function prope rly if
subjected to an impact from strong water pressure. If the vehicle
bumper strikes something, equipment may not operate properly du e to
a sensor malfunction. Have the vehicle inspected at your Toyota dealer.
● In the following situations, the sensors may not operate normally and may
lead to an accident. Drive carefully.
• Obstacles cannot be detected in the side areas until a scan of the side
areas is completed. ( P. 438)
• Even after the scan of the side areas is completed, obstacles such as other vehicles, people or animals that approach from the sides cannot
be detected.
• The sensor is frozen (if it thaws, the system returns to normal). A warning message may display at particularly low temperatures due to
the sensor freezing and it may not detect parked vehicles.
• The sensor is blocked by someone’s hand.
• The vehicle is tilted a large amount.
• The temperature is extremely hot or cold.
• The vehicle is driven on undulating roads, slopes, gravel road s, in areas
with tall grass, etc.
• An ultrasonic wave source is nearby, such as the horn or sensors of another vehicle, a motorcycle engine or the air brake of a larg e vehicle.
• Heavy rain or a water strikes the vehicle.
• The angle of the sensor may be deviated when assist control starts even if there is a parked vehicle in the target parking spot. Have the
vehicle inspected at your Toyota dealer.
• Do not install any accessories within the sensor detection ran ge.

489
PRIUS PRIME_OM_OM47C77U_(U)
5-5. Using the driving support systems
5
Driving
Driving assist systems
◆ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force co rre-
sponding to the brake operation
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenl y,
or if the brakes are applied while driving on a slippery road surface
◆Brake assist
Generates an increased level of braking force after the brake p edal
is depressed when the system de tects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or
turning on slippery road surfaces.
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippe ry
road surfaces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicl e or accelerating on slippery roads
To keep driving safety and perf ormance, the following systems
operate automatically in respon se to various driving situations.
Be aware, however, that these systems are supplementary and
should not be relied upon too heav ily when operating the vehi-
cle.

PRIUS PRIME_OM_OM47C77U_(U)
4915-5. Using the driving support systems
5
Driving
■Turning off both TRAC and VSC systems
To turn the TRAC and VSC systems off, press and hold for more than 3
seconds while the vehicle is stopped.
The VSC OFF indicator light will come on and the “Traction Cont rol Turned
Off” will be shown on the multi-information display.
*
Press again to turn the systems back on.
*: Pre-collision brake assist and pre-collision braking will also be disabled.
The PCS warning light will come on and the message will be show n on the
multi-information display. ( P. 6 6 3 )
■ When the message is displayed on the multi-information display show-
ing that TRAC has been disab led even if has not been pressed
TRAC is temporary deactivated. If the information continues to show, contact
your Toyota dealer.
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assi st control will
operate:
● The shift position is in a position other than P or N (when sta rting off forward/
backward on an upward incline)
● The vehicle is stopped
● The accelerator pedal is not depressed
● The parking brake is not engaged
■ Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
● Shift the shift position to P or N
● The accelerator pedal is depressed
● The parking brake is engaged
● No more than 2 seconds have elapsed after the brake pedal is re leased.
■ Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and
hill-start assist control systems
●A sound may be heard from the engine compartment when the brake pedal
is depressed repeatedly, when the hybrid system is started or just after the
vehicle begins to move. This sound does not indicate that a mal function has
occurred in any of these systems.
● Any of the following conditions may occur when the above system s are
operating. None of these indicates that a malfunction has occur red.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a s top.

PRIUS PRIME_OM_OM47C77U_(U)
4935-5. Using the driving support systems
5
Driving
WARNING
■The ABS does not operate effectively when
● The limits of tire gripping performance have been exceeded (such as
excessively worn tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or s lick roads.
■ Stopping distance when the ABS is operating may exceed that of nor-
mal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always
maintain a safe distance from the vehicle in front of you, especially in the
following situations:
● When driving on dirt, gravel or snow-covered roads
● When driving with tire chains
● When driving over bumps in the road
● When driving over roads with potholes or uneven surfaces
■ TRAC/VSC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRAC/VSC system is operating. D rive the
vehicle carefully in conditions where stability and power may be lost.
■ Hill-start assist control does not operate effectively when
● Do not overly rely on hill-start assist control. Hill-start ass ist control may
not operate effectively on steep inclines and roads covered wit h ice.
● Unlike the parking brake, hill-start assist control is not inte nded to hold the
vehicle stationary for an extended period of time. Do not attempt to use
hill-start assist control to hold the vehicle on an incline, as doing so may
lead to an accident.
■ When the TRAC/ABS/VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.