brake sensor Lexus IS250 2010 Owner's Manual

166
2-3. Operating the lights and windshield wipers
IS350/250_U
AFS (vehicles with discharge headlights)AFS (Adaptive Front-lighting System) improves visibility at intersections
and on curves by automatically adjusting the level of the headlights
according to vehicle speed and the degree of the tire’s angle as con-
trolled by steering input.
Operates at speeds of 6 mph (10 km/h) or higher.
■ Deactivating AFS
How to switch: →P. 3 4 2
“AFS OFF” turns on when the AFS is deactivated.
■Daytime running light system
To make your vehicle more visible to other drivers, the headlights turn on automati-
cally (at a reduced intensity) whenever the engine is started and the parking brake
is released. Daytime running lights are not designed for use at night.
■Headlight control sensor
The sensor may not function properly if an
object is placed on the sensor, or anything
that blocks the sensor is affixed to the wind-
shield.
Doing so interferes with the sensor detecting
the level of ambient light and may cause the
automatic headlight system to malfunction.

183
2-4. Using other driving systems
2
When driving
IS350/250_U
Driving in vehicle-to-vehicle distance control mode
This mode employs a radar sensor to detect the presence of vehicles up
to 400 ft. (120 m) ahead of you and to judge the distance between your
vehicle and those vehicles.
Note that vehicle-to-vehicle distance will close when traveling on long
downhill slopes.
Example of constant speed cruising (when there are no vehicles
ahead): When set to 62 mph (100 km/h)
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehi-
cle distance can also be set by operating the vehicle-to-vehicle distance
switch.
Example of deceleration cruising (when the vehicle ahead is driving
slower than the set speed): When fixed speed cruising is set at 62 mph
(100 km/h) and the vehicle ahead is driving at 50 mph (80 km/h)
When a vehicle is detected running ahead of you, in the same lane, the sys-
tem automatically decelerates your vehicle. When a greater reduction in
vehicle speed is necessary, the system applies the brakes. A warning tone
warns you when the system cannot decelerate sufficiently to prevent your
vehicle from closing on the vehicle ahead.
Example of follow-up cruising (when following a vehicle driving slower
than the set speed): When the speed is set to 62 mph (100 km/h) and
the vehicle ahead is driving at 50 mph (80 km/h)

188
2-4. Using other driving systems
IS350/250_U
CAUTION
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate control of speed and could cause an accident
resulting in death or serious injury.
●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 sharp up and
down gradients
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, etc.)
●When a buzzer can be heard often
●When your vehicle is towing a trailer
■When the radar sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the prox-
imity alarm (→P. 480) will not be activated, and an accident may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane

189
2-4. Using other driving systems
2
When driving
IS350/250_U
CAUTION
■Conditions under which the vehicle-to-vehicle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the radar sensor may
not be able to correctly detect vehicles ahead, and an accident may result.
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the trunk, etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
●When the vehicle ahead of you decelerates suddenly
■Handling the radar sensor
Observe the following to ensure the cruise control system can function effectively:
●Keep the sensor and front grille clean at all times.
Clean the sensor and front grille with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction. If the
sensor or surrounding area is subject to a strong impact, always have the area
inspected and adjusted by a Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille or surrounding area.
●Do not modify or paint the sensor and grille.
■To ensure the radar sensor functions correctly
Do not do the following to the sensor or grille cover as doing so may cause the sen-
sor not to function correctly and could result in an accident.
●Stick or attach anything to them
●Leave them dirty
●Disassemble, or subject them to strong shocks
●Modify or paint them
●Replace them with non-genuine parts

194
2-4. Using other driving systems
IS350/250_U
■Sensor detection information
●Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where this
may occur are listed below.
• There is dirt, snow or ice on the sensor.
• The sensor is frozen.
•The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle engines,air brakes of large vehicles, or other loud noises producing ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather
In addition to the examples above, there are instances in which, because of their
shapes, signs and other objects may be judged by the sensor to be closer than they
are.
●The shape of the obstacle may prevent the sensor from detecting it. Pay particu-
lar attention to the following obstacles.
• Wires, fences, ropes etc.
• Cotton, snow and other materials that absorb radio waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your
vehicle
■When the display flashes and a message is displayed
→ P. 4 8 0

202
2-4. Using other driving systems
IS350/250_U
PCS (Pre-Collision System)∗
Radar sensorDetects vehicles or other obsta-
cles on or near the road ahead and
determines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles. Grille cover
Radar sensor
Safety systems such as the brakes and seat belts are automatically
engaged to lessen impact and injuries to occupants as well as vehicle dam-
age when the radar sensor detects an unavoidable frontal collision.
■Pre-collision seat belts
If the pre-collision sensor detects that a collision is unavoidable, the pre-
collision system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or loses
control of the vehicle. ( →P. 6 4 )
■Pre-collision brake assist
Applies greater braking force in relation to how strongly the brake pedal is
depressed.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as pylons. There may also be occa-
sions when the sensor cannot detect pedestrians, animals, bicycles, motorcycles,
trees, or snowdrifts.
∗: If equipped

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2-4. Using other driving systems
2
When driving
IS350/250_U
■The pre-collision system is operational when
●Pre-collision seat belt (linked to the radar sensor):
• Vehicle speed is above 3 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncomingvehicle exceeds 18 to 24 mph (30 to 40 km/h).
• The front occupants are wearing a seat belt.
●Pre-collision seat belts (linked to brake operation):
• Vehicle speed exceeds 18 mph (30 km/h).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
●Pre-collision brake assist:
• Vehicle speed is above 18 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle is greater than 18 to 24 mph (30 to 40 km/h).
• The brake pedal is depressed.
■Conditions that may trigger the system even if there is no danger of collision
●When there is an object by the roadside at the entrance to a curve
●When passing an oncoming vehicle on a curve
●When driving over a narrow iron bridge
●When there is a metal object on the road surface
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn
●When your vehicle rapidly closes on the vehicle in front
When the system is activated in the situations described above there is also a possi-
bility that the seat belts will retract quickly and the brakes will be applied with a force
greater than normal. When the seat belt is locked in the retracted position, stop the
vehicle in a safe place, release the seat belt and refasten.
■When there is a malfunction in the system
Warning lights and/or warning messages will turn on or flash. ( →P. 4 7 1 , 4 8 0 )

5
When trouble arises
469
5-1. Essential information
IS350/250_U
Event data recorder
In a crash or a near car crash eventThe SRS airbag sensor assembly contains the EDR. In a crash or a near
car crash event, this device may record some or all of the following infor-
mation:
● Engine speed
● Whether the brake pedal was applied or not
● Ve h i c l e s p e e d
● To what extent the accelerator pedal was depressed
● Position of the transmission shift lever
● Whether the driver and front passenger wore seat belts or not
● Driver's seat position
● SRS airbag deployment data
● SRS airbag system diagnostic data
● Front passenger’s occupant classification
The information above is intended to be used for the purpose of improv-
ing vehicle safety performance. Unlike general data recorders, the EDR
does not record sound data such as conversation between passengers.
Your vehicle has computers that monitor and control certain aspects of
your vehicle. These computers assist in driving and maintaining optimal
vehicle performance.
Besides storing data useful for troubleshooting, there is an event data
recorder (EDR) that records data in a crash or a near car crash event.

565
Alphabetical index
IS350/250_U
BrakeFluid ..........................................................408
Parking brake ........................................148
Brake assist ............................................... 196
Care
Exterior ................................................... 382
Interior.....................................................385
Seat belts ............................................... 386
Cargo capacity ..................................... 206
Cargo hooks .......................................... 360
CD changer ............................................. 241
CD player.................................................. 241
Chains......................................................... 210
Child restraint system Booster seats, definition...................109
Booster seats, installation ..................116
Convertible seats, definition ..........109
Convertible seats, installation .........116
Front passenger occupant
classification system .......................104
Infant seats, definition ........................109
Infant seats, installation........................116
Installing CRS with LATCH
anchors ................................................... 114
Installing CRS with seat belts ..........116
Installing CRS with top straps .........119 Child safety
Airbag precautions ..............................99
Battery precautions ...................412, 511
Child restraint system ....................... 109
Child-protectors ................................... 44
How your child should wear
the seat belt ..........................................65
Installing child restraints..................... 113
Moon roof precautions...................... 82
Power window lock switch .............. 76
Power window precautions ............ 78
Removed electronic key
battery precautions .......................435
Seat belt comfort guide ..................... 63
Seat belt extender precautions...... 67
Seat belt precautions ..........................66
Seat heater precautions.....350, 353
Trunk precautions................................. 49
Child-protectors ...................................... 44
Cigarette lighter....................................346
Cleaning Exterior....................................................382
Interior .................................................... 385
Seat belts ............................................... 386
Clock .......................................................... 341
Coat hooks ............................................. 358
Compass ..................................................369
Condenser ............................................. 408
Console box ........................................... 334
Cooling system Engine overheating............................ 512
Cornering assist sensors .................... 190
C

570
Alphabetical index
IS350/250_U
Parking assist sensors .......................... 190
Parking brake .......................................... 148
Parking lightsReplacing light bulbs........................ 452
Switch ....................................................... 165
Wattage.................................................. 533
PCS ............................................................202
Personal lights Switch ........................................................ 331
Power outlet............................................ 347
Power windows ........................................ 76
Pre-collision system.............................202
Radar cruise control ............................. 179
Radiator ................................................... 408
Radio .......................................................... 233
RDS ............................................................235
Rear sunshade .......................................355
Rear turn signal lights Replacing light bulbs........................ 452
Wattage.................................................. 533
Rear view mirror
Compass ............................................... 369
Rear window defogger.......................228
Replacing Electronic key battery...................... 434
Fuses ........................................................ 436
Light bulbs............................................. 452
Reporting safety defects for U.S. owners ......................................... 558 Safety Connect ..................................... 373
Scuff lights................................................ 329
Seat belts
Adjusting the seat belt ........................63
Automatic locking retractor ............64
Child restraint system
installation .............................................. 113
Cleaning and maintaining
the seat belts .................................... 386
Emergency locking retractor..........64
How to wear your seat belt .............62
How your child should wear
the seat belt.......................................... 65
Pregnant women,
proper seat belt use .........................64
Reminder light......................................473
Seat belt extenders.............................. 65
Seat belt pretensioners ......................63
Seat heaters ..................................348, 351
Seat position memory............................ 57
Seat ventilators ....................................... 351
Seating capacity.................................... 209
Seats Adjustment ................................................ 51
Adjustment precautions ....................52
Child seats/child restraint
system installation .............................. 113
Cleaning ................................................ 385
Driver’s seat position memory .......53
Front passenger seat position
memory ..................................................57
Head restraint ........................................ 59
Properly sitting in the seat.................. 91
Seat heaters ...............................348, 351
Ventilated seats.................................... 351
Service reminder indicators .............157P
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