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400
PRIUS PRIME_OM_OM47D13U_(U)
5-5. Using the driving support systems
WARNING
■Before using dynamic radar cruise control with full-speed range
● Driving  safely  is  the  sole  responsibility  of  the  driver.  Do  not  rely  solely  on
the system, and drive safely by always paying careful attention  to your sur-
roundings.
● The  dynamic  radar  cruise  control  with  full-speed  range  provides  driving
assistance to reduce the driver’s burden. However, there are li mitations to
the assistance provided.
Read the following conditions carefully. Do  not overly rely on  this  system
and always drive carefully.
• When the sensor may not be correctly detecting the vehicle ahead:
P. 413
• Conditions  under  which  the  vehicle-to-vehicle  distance  control   mode
may not function correctly: P. 414
● Set the speed appropriately depending on the speed limit, traff ic flow, road
conditions, weather conditions, etc. The driver is responsible  for checking
the set speed.
● Even when the system is functioning normally, the condition of  the preced-
ing  vehicle  as  detected  by  the  system  may  differ  from  the  condition
observed  by  the  driver.  Therefore,  the  driver  must  always  remai n  alert,
assess the danger of each situation and drive safely. Relying s olely on this
system  or  assuming  the  system  ensures  safety  while  driving  can  lead  to
an accident, resulting in death or serious injury.
● Switch the dynamic radar cruise control with full-speed range o ff using the
“ON-OFF” button when not in use. 
         
        
        
     
        
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402
PRIUS PRIME_OM_OM47D13U_(U)
5-5. Using the driving support systems
WARNING
■Situations  unsuitable  for  dynamic  radar  cruise  control  with  ful l-speed
range
Do not use dynamic radar cruise control with full-speed range in any of the
following situations.
Doing so may result in inappropriate speed control and could ca use an acci-
dent resulting in death or serious injury.
● Roads where there are pedestrians, cyclers, etc.
● In heavy traffic
● On roads with sharp bends
● On winding roads
● On slippery roads, such as those covered with rain, ice or snow
● On steep downhills, or where there are sudden changes between s harp up
and down gradients 
Vehicle speed may exceed the set speed when driving down a stee p hill.
● At entrances to freeways and highways
● When weather conditions are bad enough that they may prevent the sen-
sors from detecting correctly (fog, snow, sandstorm, heavy rain, etc.)
● When  there  is  rain,  snow,  etc.  on  the  front  surface  of  the  radar  sensor  or
camera sensor
● In traffic conditions that require frequent repeated acceleration and decel-
eration
● During emergency towing
● When an approach warning buzzer is heard often 
         
        
        
     
        
        Page 403 of 792
PRIUS PRIME_OM_OM47D13U_(U)
4035-5. Using the driving support systems
5
Driving
This mode employs a radar sensor to detect the presence of vehi cles
up  to  approximately  328  ft.  (100  m)  ahead,  determines  the  curre nt
vehicle-to-vehicle following distance, and operates to maintain  a suit-
able following distance from the vehicle ahead.
Note  that  vehicle-to-vehicle  distance  will  close  in  when  traveling  on  long
downhill slopes.
Driving in vehicle-to-vehi cle distance control mode 
         
        
        
     
        
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PRIUS PRIME_OM_OM47D13U_(U)
5-5. Using the driving support systems
When constant speed control mode is selected, your vehicle will  main-
tain  a  set  speed  without  controllin g  the  vehicle-to-vehicle  distance.
Select  this  mode  only  when  vehic le-to-vehicle  distance  control mode
does not function correctly due  to a dirty radar sensor, etc.
With  the  cruise  control  off,
press  and  hold  the  “ON-OFF”
button for 1.5 seconds or more.
Immediately  after  the  “ON-OFF”
button  is  pressed,  the  radar  cruise
control  indicator  will  come  on.
Afterwards, it switches to the cruise
control indicator.
Switching  to  constant  speed  con-
trol  mode  is  only  possible  when
operating  the  lever  with  the  cruise
control off.
Accelerate  or  decelerate,  with
accelerator  pedal  operation,  to
the desired vehicle speed (at or
above  approximately  30  mph
[50  km/h])  and  push  the  lever
down to set the speed.
Cruise  control  “SET”  indicator  will
come on.
The  vehicle  speed  at  the  moment
the  lever  is  released  becomes  the
set speed.
Adjusting the speed setting:  P. 406
Canceling and resuming the speed setting:  P. 408
Selecting constant speed control mode
1
2 
         
        
        
     
        
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PRIUS PRIME_OM_OM47D13U_(U)
4115-5. Using the driving support systems
5
Driving
■Dynamic radar cruise control wi th full-speed range can be set when
● The shift position is in D.
● Vehicle speed is at or above approximately 30 mph (50 km/h).
However,  when  a  preceding  vehicle  is  detected,  the  dynamic  rada r  cruise
control  with  full-speed  range  can  be  set  even  if  the  vehicle  speed  is  at  or
below approximately 30 mph (50 km/h).
■ Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal.  After acceler-
ating,  the  set  speed  resumes.  However,  during  vehicle-to-vehicl e  distance
control mode, the vehicle speed may decrease below the set spee d in order
to maintain the distance to the preceding vehicle.
■ When the vehicle stops while follow-up cruising
●Pushing  the  lever  up  while  the  vehicle  ahead  stops  will  resume  follow-up
cruising  if  the  vehicle  ahead  starts  off  within  approximately  3   seconds  after
the lever is pushed up.
● If the vehicle ahead starts off within 3 seconds after your veh icle stops, fol-
low-up cruising will be resumed.
■ Automatic cancelation of vehicle-to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically cance led in the fol-
lowing situations:
● Actual vehicle speed falls at or below approximately 25 mph (40  km/h) when
there are no vehicles ahead.
● The  preceding  vehicle  leaves  the  lane  when  your  vehicle  is  following  at  a
vehicle  speed  at  or  below  approximately  25 mph  (40 km/h).  Other wise,  the
sensor can not properly detect the vehicle.
● VSC is activated.
● TRAC is activated for a period of time.
● When the VSC or TRAC system is turned off.
● The sensor cannot detect correctly because it is covered in some way.
● Pre-collision braking is activated.
● Intelligent Clearance Sonar is operated. (if equipped)
● The parking brake is operated.
● The vehicle is stopped by system control on a steep incline.
● The  following  are  detected  when  the  vehicle  has  been  stopped  by   system
control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.
In this situation, the shift position may automatically switch  to P. (P. 341)
If  vehicle-to-vehicle  distance  control  mode  is  automatically  ca nceled  for  any
other reason, there may be a malfunction in the system. Contact  your Toyota
dealer. 
         
        
        
     
        
        Page 413 of 792
PRIUS PRIME_OM_OM47D13U_(U)
4135-5. Using the driving support systems
5
Driving
■When the sensor may not be correctly detect ing the vehicle ahead
In  the  case  of  the  following  and  depending  on  the  conditions,  o perate  the
brake  pedal  when  deceleration  of  the  system  is  insufficient  or  operate  the
accelerator pedal when acceleration is required.
As the sensor may not be able to correctly detect these types o f vehicles, the
approach warning ( P. 409) will not be activated.
● Vehicles that cut in suddenly
● Vehicles traveling at low speeds
● Vehicles that are not moving in the same lane
● Vehicles with small rear ends (trailers with no load on board,  etc.)
● Motorcycles traveling in the same lane
● When  water  or  snow  thrown  up  by  the  surrounding  vehicles  hinders  the
detecting of the sensor
●When  your  vehicle  is  pointing  upwards
(caused  by  a  heavy  load  in  the  luggage
compartment, etc.)
● Preceding vehicle has an extremely high
ground clearance 
         
        
        
     
        
        Page 414 of 792
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PRIUS PRIME_OM_OM47D13U_(U)
5-5. Using the driving support systems
■Conditions  under  which  the  vehic le-to-vehicle  distance  control mode
may not function correctly
In the case of the following conditions, operate the brake peda l (or accelera-
tor pedal, depending on the situation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system
may not operate properly.
● When the vehicle ahead of you decelerates suddenly
● When driving on a road surrounded by a structure, such as in a  tunnel or on
a bridge
● While  the  vehicle  speed  is  decreasing  to  the  set  speed  after  th e  vehicle
accelerates by depressing the accelerator pedal
●
When the road curves or when the lanes
are narrow
● When  steering  wheel  operation  or  your
position in the lane is unstable 
         
        
        
     
        
        Page 417 of 792
417
PRIUS PRIME_OM_OM47D13U_(U)
5-5. Using the driving support systems
5
Driving
BSM (Blind Spot Monitor)
The Blind Spot Monitor is a  system that has 2 functions;
● The Blind Spot M onitor function 
Assists the driver in making t he decision when changing lanes
● The Rear Cross Traff ic Alert function 
Assists the driver when backing up
These functions use same sensors.
Outside rear view mirror indicators
Blind Spot Monitor function: 
When  a  vehicle  is  detected  in  the  blind  spot,  the  outside  rear  view  mirror
indicator  comes  on  while  the  turn  signal  lever  is  not  operated.   If  the  turn
signal  lever  is  operated  toward  the  detected  side,  the  outside  rear  view
mirror indicator flashes.
Rear Cross Traffic Alert function: 
When  a  vehicle  approaching  from  the  right  or  left  rear  of  the  vehicle  is
detected, the outside rear view mirror indicators flash.
: If equipped
Summary of the Blind Spot Monitor
1