2015 TOYOTA PRIUS Owners Manual

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When driving
●When the lane markers are yellow (These may be more difficult for the
system to recognize compared to white markers.)
● When the lane markers are broken, “Botts’ dots”, “Raised pavement
marker” or stones
● When lane markers are obscured or partially obscured by sand, dirt, etc.
● When there are shadows on the road running parallel with lane markers,
or if a shadow covers the lane markers
● When driving on a particularly bright road surface, such as concrete
● When driving on a road surface that is bright due to reflected light
● When driving in a location where the light level changes rapidly, such as
the entrance to or exit from a tunnel
● When sunlight or the headlights of oncoming vehicles are shining directly
into the camera lens
● When driving on roads that are branching or merging
● When driving on a road surface that is wet due to rain, previous rainfall,
standing water, etc.
● When the vehicle experiences strong up-and-down motion such as when
driving on an extremely rough road or on a seam in the pavement
● When headlight brightness at nighttime is reduced due to dirt on the
lenses, or when the headlights are misaligned
● When driving with a strong crosswind
● When driving on winding roads or roads that are uneven
● When driving on rough or unpaved roads
■ When changing the tires
Depending on the tires used, sufficient performance may not be maintain-
able.
■ Warning messages for LKA
Warning messages are used to indicate a system malfunction or to inform
the driver of the need for caution while driving. (P. 521, 524)

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CAUTION
■Before using the LKA system
Do not rely solely on the LKA system. The LKA system does not drive the
vehicle automatically, nor does it reduce the amount of care you need to
take. As such, the driver must always assume full responsibility for under-
standing his/her surroundings, for operating the steering wheel to correct the
driving line, and for driving safely.
Inappropriate or negligent driving could lead to an accident.
■ To avoid operating the LKA by mistake
Switch the LKA off using the “LKA” switch when not in use.
■ Situations unsuitable for LKA
Do not use LKA in any of the following situations.
Otherwise, the system may not function correctly and could result in an acci-
dent.
●When driving with snow tires, tire c hains, a spare tire, or similar equipment
● When the tires have been excessively worn, or when the tire inflation pres-
sure is low.
● When there are objects or structures along the roadside that might be mis-
interpreted as lane markers (such as guardrails, curb, reflector posts, etc.)
● When driving on snowy roads
● When pavement lane markers are difficult to see due to rain, snow, fog,
etc.
● When there are visible lines on the pavement from road repairs, or if the
remains of old lane markers are still visible on the road
● When driving on slippery roads, such as those covered with rain, ice or
snow
● When driving in a lane other than the driving or passing lanes on a freeway
or highway
● When driving on a road with lane closures due to maintenance, or when
driving in a temporary lane
● During emergency towing

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NOTICE
■To prevent damage to or incorr ect operation of the LKA system
● Do not modify the headlights or attach stickers to the surface of the lights.
● Do not modify the suspension or sun visor, or replace them with non-genu-
ine parts.
● Do not install or place anything on the hood or the grille. Also, do not install
a grille guard (bull bars, kangaroo bar etc.).
● Do not modify the sun visor or replace it with anything other than a genu-
ine Toyota product.
● If your windshield needs repairs, contact your Toyota dealer.
■ Camera sensor (P. 290)
Observe the following to ensure that the LKA system functions correctly.
●Keep the windshield clean at all times.
Performance could be affected if the windshield is dirty, or if raindrops,
condensation or ice are adhering to the windshield.
● When adjusting the rear view mirror, make sure that it does not block the
camera lens.
● Do not attach window tinting to the windshield.
● Do not install an antenna in front of the camera lens.
● If the windshield is fogged up, use the windshield defogger to remove fog
from the windshield.
When it is cold, using the heater with air blowing to the feet may allow the
upper part of the windshield to fog up. This will have a negative effect on
the images.
●Do not attach a sticker or other items to
the windshield near the camera sensor.
● Do not install or place anything near the
camera.

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NOTICE
●Do not place anything on the dashboard.
The camera sensor may recognize the image reflected on the windshield
as lane markers by mistake.
● Do not scratch the camera lens, or let it get dirty.
When cleaning the inside of the windshield, be careful not to get any glass
cleaner etc. on the lens. Also, do not touch the lens.
For lens repair, contact your Toyota dealer.
● Do not change the installation position or direction of the camera sensor or
remove it. The direction of the camera sensor is precisely adjusted.
● Do not subject the camera sensor to strong impact or force, and do not
disassemble the camera sensor.

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Driving assist systems
To help enhance driving safety and performance, the following sys-
tems operate automatically in res ponse to various driving situations.
Be aware, however, that these systems are supplementary and
should not be relied upon too heavi ly when operating the vehicle.
■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 spin-
ning 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
■Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controlling steering performance.

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When the TRAC/VSC/ABS systems are operatingThe slip indicator light will flash
while the TRAC/VSC/ABS sys-
tems are operating.
■Hill-start assist control
P. 306
■PCS (Pre-Collision System) (if equipped)
P. 308

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■Sounds and vibrati ons caused by the ABS, brake assist, VSC and
TRAC
● A sound may be heard from the engine compartment when the hybrid
system is started, just after the vehicle begins to move, if the brake pedal
is depressed forcefully or repeatedly, or 1-2 minutes after the hybrid sys-
tem is stopped. This sound does not indicate that a malfunction has
occurred in any of these systems.
● Any of the following conditions may occur when the above systems are
operating. 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 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.
■ EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may
be heard. This does not indicate a malfunction.
■ 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.
*: If the LKA (Lane-Keeping Assist) system (if equipped) cannot operate in this case, a warning message will be shown on the multi-information dis-
play.
■ Electric power steering system warning light (warning buzzer)
P. 5 1 1

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CAUTION
■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 fol-
lowing 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 may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be
lost.
■ When the 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.