2018 TOYOTA PRIUS stop start

388
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
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 according 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 16 mph (30 km/h).
→Operate the switch when the vehicle speed is
approximately 16 mph (30 km/h) or less.

390
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
■When the operation is canceled
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.
The vehicle is moved and assist control is started
while the steering wheel is held.
→Stop the vehicle and fo llow the guidance pro-
vided by the system to start assist control.
MessageSituation•Handling method
MessageSituation•Handling method
While assist control is operating, the driver changes
the shift position to P or operates the S-APGS
switch.
The vehicle speed exceeds 16 mph (30 km/h) when
searching for a parallel parking assist mode space.
Assist control is started in an area with narrow park-
ing spaces.
The shift position is changed without having used
the turn signal lever to select a departure direction
when using the exit parallel parking assist mode.
→ Follow the guidance provided by the system.
When assist control starts, the vehicle proceeds in a
direction opposite to the guidance.
→Follow the guidance provided by the system
to proceed forward.

PRIUS_OM_OM47B89U_(U)
3914-5. Using the driving support systems
4
Driving
■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.

PRIUS_OM_OM47B89U_(U)
3974-5. Using the driving support systems
4
Driving
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 properly if
subjected to an impact from strong water pressure. If the vehicle
bumper strikes something, equipment may not operate properly due 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. 345)
• 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 r oads, slopes, gravel roads, 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 large 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 range.

408
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
Driving assist systems
◆ECB (Electronically Controlled Brake System)
The electronically controlled system generates braking force corre-
sponding to the brake operation
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly,
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 pedal
is depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or
turning on slippery road surfaces
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicle or accelerating on slippery roads
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel
To help enhance driving safety and performance, the following
systems operate automatically in response to various driving
situations. Be aware, however, that these systems are supple-
mentary and should not be relied upon too heavily when operat-
ing the vehicle.

PRIUS_OM_OM47B89U_(U)
4114-5. Using the driving support systems
4
Driving
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and
hill-start assist control systems
Any of the following conditions may occur when the above systems are oper-
ating. None of these indicates that a malfunction has occurred.
●Vibrations may be felt through the vehicle body and steering.
● A motor sound may be heard also after the vehicle comes to a stop.
● The brake pedal may pulsate slightly after the ABS is activated.
● The brake pedal may move down slightly after the ABS is activated.
■ ECB operating sound
ECB operating sound may be heard in the following cases, but it does not
indicate that a malfunction has occurred.
●Operating sound heard from the engine compartment when the brake pedal
is operated.
● Motor sound of the brake system heard from the front part of the vehicle
when the driver’s door is opened.
● Operating sound heard from the engine compartment when 1 or 2 minutes
passed after the stop of the hybrid system.
■ EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.

412
PRIUS_OM_OM47B89U_(U)
4-5. Using the driving support systems
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering wheel may feel heavy as a result. Should this occur, refrain
from excessive steering input or stop the vehicle and turn the hybrid system
off. The EPS system should return to normal within 10 minutes.
■ Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
● When the power switch is turned off
● If only the TRAC system is turned off, the TRAC will turn on when vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-enabling will
not occur when vehicle speed increases.
■ Electric power steering system warning light (warning buzzer)
→P. 674
■ Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will
operate:
● The shift position is in a position other than P or N (when starting 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
● Approximately 2 seconds elapse after the brake pedal is released

PRIUS_OM_OM47B89U_(U)
4134-5. Using the driving support systems
4
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 slick road.
■ 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 systems are operating.
Drive 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 the hill-start assist control. The hill-start assist control
may not operate effectively on steep inclines and roads covered with ice.
● Unlike the parking brake, hill-start assist control is not intended 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, VSC an d/or ABS is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.