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◆Pre-collision warning
When the system determines that
the possibility of a frontal collision is
high, a buzzer will sound and a warn-
ing message will be displayed on the
multi-information display to urge the
driver to take evasive action.
◆Pre-collision brake assist
When the system determines that the po ssibility of a frontal collision is high,
the system applies greater braking force in relation to how strongly the brake
pedal is depressed.
PCS (Pre-Collision System)
: If equipped
The pre-collision system uses a rada r sensor and camera sensor to detect
vehicles and pedestrians*1 in front of your vehicle. When the system deter-
mines that the possibility of a frontal collision with a vehicle or pedestrian is
high, a warning operates to urge the driver to take evasive action and the
potential brake pressure is increased to help the driver avoid the collision. If
the system determines that the possibility of a frontal collision with a vehicle or
pedestrian is extremely high, the brakes are automatically applied*2 to help
avoid the collision or help reduce the impact of the collision.
The pre-collision system can be disabl ed/enabled and the warning timing can
be changed. ( P. 269)
*1: Depending on the region in which the vehicle was sold, the pedestrian detection
function may not be available. Contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer for details.
*2: Depending on the region in which the ve hicle was sold, the pre-collision braking
function (automatic braking function) may not be available. Contact any authorized
Lexus retailer or Lexus authorized repair er, or any reliable repairer for details.
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◆Pre-collision braking*3
When the system determines that the possibility of a frontal collision is high,
the system warns the driver. If the syst em determines that the possibility of a
frontal collision is extremely high, the br akes are automatically applied to help
avoid the collision or reduce the collision speed.
*3: Depending on the region in which the vehi cle was sold, the pre-collision braking func-
tion may not be available.
◆Suspension control (if equipped)
When the system determines that the po ssibility of a frontal collision is high,
the Adaptive Variable Suspension System ( P. 353) will control the damping
force of the shock absorbers to help ma intain an appropriate vehicle posture.
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WARNING
■Limitations of the pre-collision system
●The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Do not use the pre-collision sy stem instead of normal braking operations under any circumstances. This system will not preven t collisions or lessen collision damage or
injury in every situation. Do not overly rely on this system. Failure to do so may lead to
an accident, resulting in death or serious injury.
●Although this system is designed to help avoid a collision or help reduce the impact of
the collision, its effectiveness may change according to various conditions, therefore
the system may not always be able to achieve the same level of performance. Read the following cond itions carefully. Do not overly rely on this system and always
drive carefully.
• Conditions under which the system may oper ate even if there is no possibility of a collision: P. 274
• Conditions under which the syst em may not operate properly: P. 276
●Do not attempt to test the operation of the pre-collision system yourself, as the system
may not operate properly, possib ly leading to an accident.
■Pre-collision braking*3
●When the pre-collision braking function is operating, a large amount of braking force
will be applied.
●If the vehicle is stopped by the operation of the pre-collision braking function, the pre- collision braking function operation will be canceled after approximately 2 seconds.
Depress the brake pedal as necessary.
●The pre-collision braking function may no t operate if certain operations are per- formed by the driver. If the accelerator pedal is being depressed strongly or the steer-
ing wheel is being turned, the system may determine that the driver is taking evasive
action and possibly prevent the pre-coll ision braking function from operating.
●In some situations, while the pre-collision braking function is operating, operation of
the function may be canceled if the accelerator pedal is depressed strongly or the
steering wheel is turned and the system dete rmines that the driver is taking evasive action.
●If the brake pedal is being depressed, the system may determine that the driver is tak-
ing evasive action and possibly delay the op eration timing of the pre-collision braking function.
*3: Depending on the region in which the vehicle was sold, the pre-collision braking
function may not be available.
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WARNING
■When to disable the pre-collision system
In the following situations, disable the system, as it may not operate properly, possibly
leading to an accident resultin g 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 on and the tires are allowed to rotate freely
●When inspecting the vehicle using a drum tester such as a chassis dynamometer or
speedometer tester, or when using an on vehicle wheel balancer
●When a strong impact is applied to the fron t 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 vehicle 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 camera sensor is
temporarily installe d to the vehicle
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IS300h_EE(OM53D89E)
■Enabling/disabling the pre-collision system
The pre-collision system can be enabled/disabled on ( P. 119) of the
multi-information display.
The system is automatically enabled each time the power switch is turned to ON
mode.
If the system is disabled, the PCS
warning light will turn on and a mes-
sage will be displayed on the multi-
information display.
■Changing the pre-collision warning timing
The pre-collision warning timing can be changed on ( P. 119) of the
multi-information display.
The operation timing setting is retained when the power switch is turned off.
Far
The warning will begin to operate earlier than with the default timing.
Middle
This is the default setting.
Near
The warning will begin to operatelater than with the default timing.
Changing settings of the pre-collision system
1
2
3
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2704-5. Using the driving support systems
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■Operational conditions
Availability of the pedestrian detection function and pre-collision braking function
depend on the region in which the vehicle was sold.
Read the following for details:
Region A (The pedestrian detection function and pre-collision braking function are available)
The pre-collision system is enabled and the sy stem determines that the possibility of a
frontal collision with a vehicle or pedestrian is high.
Each function is operationa l at the following speeds:
●Pre-collision warning:
• Vehicle speed is between approximately 10 and 180 km/h (7 and 110 mph). (For detecting a pedestrian, vehicle speed is between approximately 10 and 80 km/h [7
and 50 mph].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 10 km/h (7 mph) or more.
●Pre-collision brake assist:
• Vehicle speed is between approximately 30 and 180 km/h (19 and 110 mph). (For
detecting a pedestrian, vehicle speed is between approximately 30 and 80 km/h
[19 and 50 mph].) • The relative speed between your vehicle and the vehicle or pedestrian ahead is
approximately 30 km/h (19 mph) or more.
●Pre-collision braking:
• Vehicle speed is between approximately 10 and 180 km/h (7 and 110 mph). (For
detecting a pedestrian, vehicle speed is between approximately 10 and 80 km/h [7 and 50 mph].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is
approximately 10 km/h (7 mph) or more.
The system may not operate in the following situations:
●If a 12-volt battery terminal has been disconnected and reconnected and then the vehi-
cle has not been driven for a certain amount of time
●If the shift lever is in R
●If VSC is disabled (only the pre-collis ion warning function will be operational)
●If the PCS warning light is flashing or illuminated
RegionsFunction availability
Region AThe pedestrian detection function and pre-collision braking function are available
Region BThe pedestrian detection function is not available and the pre-
collision braking function is available
Region CThe pedestrian detection func tion and pre-collision braking
function are not available
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Region B
(The pedestrian detection function is not available and the pre-collision braking func- tion is available)
The pre-collision system is enabled and the sy stem determines that the possibility of a
frontal collision with a vehicle is high.
Each function is operationa l at the following speeds:
●Pre-collision warning:
• Vehicle speed is between approximately 15 and 180 km/h (10 and 110 mph). • The relative speed between your vehicle and the vehicle ahead is approximately 10
km/h (7 mph) or more.
●Pre-collision brake assist:
• Vehicle speed is between approximately 30 and 180 km/h (19 and 110 mph).
• The relative speed between your vehicle and the vehicle ahead is approximately 30 km/h (19 mph) or more.
●Pre-collision braking:
• Vehicle speed is between approximately 15 and 180 km/h (10 and 110 mph).
• The relative speed between your vehicle and the vehicle ahead is approximately 10
km/h (7 mph) or more. The system may not operate in the following situations:
●If a 12-volt battery terminal has been disconnected and reconnected and then the vehi-
cle has not been driven for a certain amount of time
●If the shift lever is in R
●If VSC is disabled (only the pre-collis ion warning function will be operational)
●If the PCS warning light is flashing or illuminated
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Region C
(The pedestrian dete ction function and pre-collision braking function are not avail- able)
The pre-collision system is enabled and the sy stem determines that the possibility of a
frontal collision with a vehicle is high.
Each function is operationa l at the following speeds:
●Pre-collision warning:
• Vehicle speed is between approximately 15 and 180 km/h (10 and 110 mph). • The relative speed between your vehicle and the vehicle ahead is approximately 10
km/h (7 mph) or more.
●Pre-collision brake assist:
• Vehicle speed is between approximately 30 and 180 km/h (19 and 110 mph).
• The relative speed between your vehicle and the vehicle ahead is approximately 30 km/h (19 mph) or more.
The system may not operate in the following situations:
●If a 12-volt battery terminal has been disconnected and reconnected and then the vehi- cle has not been driven for a certain amount of time
●If the shift lever is in R
●If VSC is disabled (only the pre-collis ion warning function will be operational)
●If the PCS warning light is flashing or illuminated