
PRIUS_OM_OM47E09U_(U)
2994-5. Using the driving support systems
4
Driving
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 ser ious 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 on  and the tires
are allowed to rotate freely
● When inspecting the vehicle using a drum tester such as a chass is dyna-
mometer  or  speedometer  tester,  or  when  using  an  on  vehicle  whee l  bal-
ancer
● When a strong impact is applied to the front bumper or front gr ille, 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 sens or or front
camera is temporarily installed to the vehicle 

308
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
WARNING
■Before using LTA system
● Do  not  rely  solely  upon  the  LTA  system.  The  LTA  system  does  not   auto-
matically  drive  the  vehicle or reduce the amount  of attention that must be
paid to the area in front of the vehicle. The driver must always assume full
responsibility for driving safely by paying careful attention to the surround-
ing  conditions  and  operating  the  steering  wheel  to  correct  the  path  of  the
vehicle. Also,  the  driver  must  take  adequate  breaks  when  fatigu ed,  such
as from driving for a long period of time.
● Failure to perform appropriate driving operations and pay caref ul attention
may lead to an accident, resulting in death or serious injury.
● When not using the LTA system, use the LTA switch to turn the system off.
■ Situations unsuitable for LTA system
In the following situations, use the LTA switch to turn the system off. Failure
to do so may lead to an accident, resulting in death or serious injury.
● Vehicle is driven on a road surface which is slippery due to rainy weather,
fallen snow, freezing, etc.
● Vehicle is driven on a snow-covered road.
● White (yellow) lines are difficult to see due to rain, snow, fo g, dust, etc.
● Vehicle is driven in a temporary lane or restricted lane due to  construction
work.
● Vehicle is driven in a construction zone.
● A spare tire, tire chains, etc. are equipped.
● When the tires have been excessively worn, or when the tire inf lation pres-
sure is low.
● During emergency towing.
■ Preventing  LTA  system  malfunctions  and  operations  performed  by
mistake
● Do  not  modify  the  headlights  or  place  stickers,  etc.  on  the  sur face  of  the
lights.
● Do  not  modify  the  suspension  etc.  If  the  suspension  etc.  needs  to  be
replaced, contact your Toyota dealer.
● Do not install or place anything on the hood or grille. Also, d o not install a
grille guard (bull bars, kangaroo bar, etc.).
● If your windshield needs repairs, contact your Toyota dealer. 

418
PRIUS_OM_OM47E09U_(U)
4-5. Using the driving support systems
WARNING
●Do  not  use  the  system  in  the  following  situations,  as  the  syste m  may  be
unable to correctly assist you in reaching the target parking s pot and may
lead to an unexpected accident.
• In an area that is not a parking lot
• A parking lot that is not paved and has no parking space lines, such as a sand or gravel parking lot
• A parking lot that has a slope or undulations in the road
• A frozen, snow-covered or slippery road
• The asphalt is melting due to hot weather
• There is an obstacle between the vehicle and the target parking spot
• Using tire chains or compact spare tire (if equipped)
● Do  not use  tire  other  than that provided  by the manufacturer. The  system
may  not  operate  properly.  When  replacing  tires,  contact  your  Toyota
dealer.
● The system may not be able position the vehicle in the set location in the
following situations.
• The tires are extremely worn or the tire pressure is low
• The vehicle is carrying very heavy load
• The  vehicle  is  tilted  due  to  having  luggage,  etc.  located  on  one  side  of
the vehicle
• There  are  road  heaters  installed  in  the  parking  lot  to  prevent   the  road
surface from freezing.
In  any  other  situations  when  the  set  position  and  vehicle  posit ion  greatly
differ, have the vehicle inspected by your Toyota dealer.
● Make sure to observe the following precautions regarding the exit parallel
parking assist mode.
Exit parallel parking assist mode is a function used when depar ting from a
parallel  parking  spot.  However,  this  function  may  not  be  usable  if  obsta-
cles  or  people  are  detected  in  front  of  the  vehicle.  Only  use  t his  function
when departing from a parallel parking spot. In the event that the steering
control  operates,  either  turn  the  system  off  using  the  S-APGS  s witch  or
operate the steering wheel to stop the control.
● If exit parallel parking assist mode is mistakenly used in the  following situ-
ations, the vehicle may make contact with an obstacle.
The  departure  function  is  operated  in  a  direction  where  an  obst acle  is
present,  but  the  obstacle  is  not  detected  by  the  side  sensors  ( situations
such as when the vehicle is directly beside a pole). 

PRIUS_OM_OM47E09U_(U)
4254-5. Using the driving support systems
4
Driving
WARNING
■The ABS does not operate effectively when
● The  limits  of  tire  gripping  performance  have  been  exceeded  (suc h  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,  espe cially  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 b e lost.
■ Active Cornering Assist does  not operate effectively when
● Do not overly rely on Active Cornering Assist. Active Cornering  Assist may
not  operate  effectively  when  accelerating  down  slopes  or  driving  on  slip-
pery road surfaces.
● When  Active  Cornering  Assist  frequently  operates,  Active  Corner ing
Assist  may  temporarily  stop  operating  to  ensure  proper  operatio n  of  the
brakes, TRAC and VSC.
■ 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. 

430
PRIUS_OM_OM47E09U_(U)
4-6. Driving tips
Winter driving tips
●Use  fluids  that  are  appropriate  t o  the  prevailing  outside  tempera-
tures.  • Engine oil
• Engine/power control unit coolant
• Washer fluid
● Have  a  service  technician  inspect  the  condition  of  the  12-volt  bat-
tery.
● Have the vehicle fitted with four snow tires or purchase a set  of tire
chains for the  front tires. 
Ensure  that  all  tires  are  the  same  size  and  brand,  and  that  cha ins  match
the size of the tires.
Perform the following accordi ng to the driving conditions:
● Do not try to forcibly open a window or move a wiper that is fr ozen.
Pour  warm  water  over  the  frozen  area  to  melt  the  ice.  Wipe  away
the water immediately to p revent it from freezing. 
● To  ensure  proper  operation  of  the  climate  control  system  fan,
remove  any  snow  that  has  accumulated  on  the  air  inlet  vents  in
front of the windshield. 
● Check for and remove any excess ic e or snow that may have accu-
mulated  on  the  exterior  lights,  vehicle’s  roof,  chassis,  around  the
tires or on the brakes.
● Remove  any  snow  or  mud  from  the  bottom  of  your  shoes  before
getting in the vehicle.
Carry  out  the  necessary  preparations  and  inspections  before
driving  the  vehicle  in  winter. Always  drive  the  vehicle  in  a  ma n-
ner appropriate to the prevailing weather conditions. 
Preparation for winter
Before driving the vehicle 

432
PRIUS_OM_OM47E09U_(U)
4-6. 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 tir e chains on the rear
tires.
● Install tire chains on front tires as tightly as possible. Reti ghten chains after
driving 1/4 - 1/2 mile (0.5 - 1.0 km).
● Install tire chains following the instructions provided with th e tire chains. 
WARNING
■Driving with snow tires
Observe the following precautions to reduce the risk of acciden ts. 
Failure  to  do  so  may  result  in  a  loss  of  vehicle  control  and  ca use  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 acciden ts. 
Failure  to  do  so  may  result  in  the  vehicle  being  unable  to  be  d riven  safely,
and may cause death or serious injury.
● Do not drive in excess of the speed limit specified for the tir e 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 v ehicle con-
trol is maintained.
● Do not use LTA (Lane Tracing Assist) (if equipped).
■ When parking the vehicle
When parking the vehicle without applying the parking brake, ma ke sure to
chock  the  wheels.  If  you  do  not  chock  the  wheels,  the  vehicle  m ay  move
unexpectedly, possibly resulting in an accident. 

PRIUS_OM_OM47E09U_(U)
4334-6. Driving tips
4
Driving
NOTICE
■Repairing or replacing snow tires
Request  repairs  or  replacement  of  snow  tires  from Toyota  dealer s  or  legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affect s the opera-
tion of the tire pressure warning valves and transmitters.
■ Fitting tire chains
The tire pressure warning valves and transmitters may not funct ion correctly
when tire chains are fitted. 

PRIUS_OM_OM47E09U_(U)
5376-3. Do-it-yourself maintenance
6
Maintenance and care
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway
driving under dry conditions. Si nce summer tires do not have th e 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  sno w  and  to
be  adequate  for  driving  in  most  winter  conditions  as  well  as  fo r  use
year-round.  All  season  tires,  however,  do  not  have  adequate  tra ction
performance compared with snow tires in heavy or loose snow. Al so, all
season  tires  fall  short  in  acceleration  and  handling  performanc e  com-
pared with summer tires in highway driving.
●Snow tires
For  driving  on  snow-covered  roads  or  icy  roads,  we  recommend  us ing
snow  tires.  If  you  need  snow  tires,  select  tires  of  the  same  si ze,  con-
struction  and  load  capacity  as  t he  originally  installed  tires. Since  your
vehicle  has  radial  tires  as  original  equipment,  make  sure  your  snow
tires  also  have  radial  construct ion.  Do  not  install  studded  tires  without
first  checking  local  regulations  for  possible  restrictions.  Sno w  tires
should be install ed on all wheels. ( P. 430)
■If the tread on snow tires wea rs down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■Low profile tires (vehicl es with 215/45R17 tires)
Generally,  low  profile  tires  will  wear  more  rapidly  and  tire  gr ip  perfor-
mance  will  be  reduced  on  snowy  and /or  icy  roads  when  compared  to
standard tires.
Be  sure  to  use  snow  tires  or  tire  chains  on  snowy  and/or  icy  roads  and
drive carefully at a speed approp riate for road and weather conditions.