372
PRIUS PRIME_OM_OM47A88U_(U)
5-5. Using the driving support systems
WARNING
■When to disable the pre-collision system
In the following situations, disable the system, as it may not operate prop-
erly, possibly leading to an accident resulting in death or serious injury:
● When the vehicle is being towed
● When your vehicle is towing another vehicle
● When transporting the vehicle via truck, boat, train or similar means of
transportation
● When the vehicle is raised on a lift with the hybrid system operating and
the tires are allowed to rotate freely
● When inspecting the vehicle using a drum tester such as a chassis dyna-
mometer or speedometer tester, or when using an on vehicle wheel bal-
ancer
● When a strong impact is applied to the front bumper or front grille, due to
an accident or other reasons
● If the vehicle cannot be driven in a stable manner, such as when the vehi-
cle has been in an accident or is malfunctioning
● When the vehicle is driven in a sporty manner or off-road
● When the tires are not properly inflated
● When the tires are very worn
● When tires of a size other than specified are installed
● When tire chains are installed
● When a compact spare tire or an emergency tire puncture repair kit is used
● If equipment (snow plow, etc.) that may obstruct the radar sensor or cam-
era sensor is temporarily installed to the vehicle
PRIUS PRIME_OM_OM47A88U_(U)
3755-5. Using the driving support systems
5
Driving
■Pedestrian detection function
■ Cancelation of the pre-collision braking
If either of the following occur while the pre-collision braking function is oper-
ating, it will be canceled:
●The accelerator pedal is depressed strongly.
● The steering wheel is turned sharply or abruptly.
■ Conditions under which the system ma y operate even if there is no pos-
sibility of a collision
● In some situations such as the following, the system may determine that
there is a possibility of a frontal collision and operate.
• When passing a vehicle or pedestrian
• When changing lanes while overtaking a preceding vehicle
• When overtaking a preceding vehicle that is changing lanes
The pre-collision system detects pedestri-
ans based on the size, profile, and motion
of a detected object. However, a pedes-
trian may not be detected depending on
the surrounding brightness and the
motion, posture, and angle of the
detected object, preventing the system
from operating properly. (→P. 379)
• When overtaking a preceding vehiclethat is making a left/right turn
• When passing a vehicle in an oncom- ing lane that is stopped to make a
right/left turn
PRIUS PRIME_OM_OM47A88U_(U)
3795-5. Using the driving support systems
5
Driving
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or camera sensor 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
● Some pedestrians such as the following may not be detected by the radar
sensor and camera sensor, preventing the system from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or taller than approx-
imately 6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skirt, etc.), mak-
ing their silhouette obscure
• Pedestrians who are carrying large baggage, holding an umbrella, etc., hiding part of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller, wheelchair, bicycle or other vehi-
cle
• Groups of pedestrians which are close together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to be nearly the same color or brightness as their surroundings
• Pedestrians near walls, fences, guardrails, or large objects
• Pedestrians who are on a metal object (manhole cover, steel plate, etc.) on the road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly
• Pedestrians running out from behind a vehicle or a large object
• Pedestrians who are extremely close to the side of the vehicle (outside
rear view mirror, etc.)
• If the front of the vehicle is raised or
lowered
PRIUS PRIME_OM_OM47A88U_(U)
4815-5. Using the driving support systems
5
Driving
WARNING
■When the TRAC/VSC syst ems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are the systems to help ensure vehicle stability and driving
force, do not turn the TRAC/VSC systems off unless necessary.
■ Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and
total load capacity. In addition, make sure that the tires are inflated to the
recommended tire inflation pressure level.
The ABS, TRAC and VSC systems will not function correctly if different tires
are installed on the vehicle.
Contact your Toyota dealer for further information when replacing tires or
wheels.
■ Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect
the driving assist systems, and may cause a system to malfunction.
PRIUS PRIME_OM_OM47A88U_(U)
4835-6. Driving tips
5
Driving
Accelerate the vehicle slowly, keep a safe distance between you and
the vehicle ahead, and drive at a reduced speed suitable to road con-
ditions.
Park the vehicle and shift the shift position to P and block the wheel
under the vehicle without setting t he parking brake. The parking brake
may freeze up, preventing it from being released. If the vehicle is
parked without setting the parking brake, make sure to block the
wheels.
Failure to do so may be dangerous because it may cause the vehicle
to move unexpectedly, possibly leading to an accident.
Use the correct tire chain size when mounting the tire chains. Chain
size is regulated for each tire size.
Side chain
0.12 in. (3.0 mm)
1.18 in. (30.0 mm)
0.39 in. (10.0 mm)
Cross chain 0.16 in. (4.0 mm)
0.98 in. (25.0 mm)
0.55 in. (14.0 mm)
Regulations regarding the use of tire chains vary depending on loca-
tion and type of road. Al ways check local regulations before installing
chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
1
2
3
4
5
6
Regulations on the use of tire chains
484
PRIUS PRIME_OM_OM47A88U_(U)
5-6. Driving tips
■Tire chain installation
Observe the following precautions when installing and removing chains:
●Install and remove tire chains in a safe location.
● Install tire chains on the front tires only. Do not install tire chains on the rear
tires.
● Install tire chains on front tires as tightly as possible. Retighten chains after
driving 1/4 - 1/2 mile (0.5 - 1.0 km).
● Install tire chains following the instructions provided with the tire ch\
ains.
■ Consumption of fuel and electricity
In cold temperatures, resistance of the parts of a vehicle (transmission, tires,
etc.) generally increases, resulting in increase of energy consumption. As a
result, fuel economy is likely to decrease.
Consumption of fuel and electricity of this vehicle is also likely to become
worse in cold temperatures.
WARNING
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in a loss of vehicle control and cause death or
serious injury.
● Use tires of the specified size.
● Maintain the recommended level of air pressure.
● Do not drive in excess of 75 mph (120 km/h), regardless of the type of
snow tires being used.
● Use snow tires on all, not just some wheels.
■ Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failure to do so may result in the vehicle being unable to be driven safely,
and may cause death or serious injury.
● Do not drive in excess of the speed limit specified for the tire chains being
used, or 30 mph (50 km/h), whichever is lower.
● Avoid driving on bumpy road surfaces or over potholes.
● Avoid sudden acceleration, abrupt steering, sudden braking and shifting
operations that cause sudden engine braking.
● Slow down sufficiently before entering a curve to ensure that vehicle con-
trol is maintained.
■ When parking the vehicle
When parking the vehicle without applying the parking brake, make sure to
chock the wheels. If you do not chock the wheels, the vehicle may move
unexpectedly, possibly resulting in an accident.
PRIUS PRIME_OM_OM47A88U_(U)
5977-3. Do-it-yourself maintenance
7
Maintenance and care
■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to
expose the fabric, and bulges indicating internal damage.
●A tire goes flat repeatedly or cannot be properly repaired due to the size
or location of a cut or other damage.
If you are not sure, consult with your Toyota dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not reg-
istered, the tire pressure warning system will not work properly. After driv-
ing for about 20 minutes, the tire pressure warning light blinks for 1
minute and stays on to indicate a system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even
if it has seldom or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation
pressure checks. Make su re to check tire inflation pressure as part of
your routine of daily vehicle checks.
■Maximum load of tire
Check that the maximum load of the re placement tire is greater than 1/2
of the Gross Axle Weight Ratings (GAWR) of either the front axle or the
rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. ( →P. 721)
598
PRIUS PRIME_OM_OM47A88U_(U)
7-3. Do-it-yourself maintenance
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway
driving under dry conditions. Since summer tires do not have the same
traction performance as snow tires, summer tires are inadequate for
driving on snow-covered or icy ro ads. For driving on snow-covered
roads or icy roads, the use of snow tires is recommended. When install-
ing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to
be adequate for driving in most winter conditions as well as for use
year-round. All season tires, however, do not have adequate traction
performance compared with snow tires in heavy or loose snow. Also, all
season tires fall short in acceleration and handling performance com-
pared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using
snow tires. If you need snow tires, select tires of the same size, con-
struction and load capacity as the or iginally installed tires. Since your
vehicle has radial tires as original equipment, make sure your snow
tires also have radial construction. Do not install studded tires without
first checking local regulations fo r possible restrictions. Snow tires
should be installed on all wheels. ( →P. 482)
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tire s as snow tires is lost.