REV Lexus IS250 2015 Workshop Manual

2054-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
CAUTION
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not appropriate,
adjust the vehicle speed, as well as the distance between your vehicle and vehicles
ahead by applying the brakes etc.
■Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
●Assisting the driver to measure following distance
The dynamic radar cruise control is only intended to help the driver in determining
the following distance between the driver’s own vehicle and a designated vehicle
traveling ahead. It is not a mechanism that a llows careless or inattentive driving, and it
is not a system that can assist the driver in low-visibility conditions. It is still necessary
for driver to pay close attention to the vehicle’s surroundings.
●Assisting the driver to judg e proper following distance
The dynamic radar cruise control determines whether the following distance
between the driver’s own vehicle and a designated vehicle traveling ahead is appro-
priate or not. It is not capable of making any other type of judge ment. Therefore, it is
absolutely necessary for the driver to remain vigilant and to determine whether or not
there is a possibility of dang er in any given situation.
●Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a collision with
a vehicle traveling ahead. Therefore, if there is ever any danger, the driver must take
immediate and direct control of the vehicle and act appropriately in order to ensure
the safety of all involved.
■To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON/OFF” button when not in use.

2064-5. Using the driving support systems
IS350/250_U (OM53C50U)
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 speed control and could cause an accident result-
ing 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 su dden changes between sharp up and down
gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors from
functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
●When an approach warning buzzer is heard often
●During emergency towing
■When the 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 approach
warning ( →P. 201) will not be activated, and a fatal or serious 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
■Conditions under which the ve hicle-to-vehicle distance control may not function cor-
rectly
Apply the brakes as necessary in the following conditions as the radar sensor may not
be able to correctly detect vehicles ahead, and a fatal or serious accident may result:
●When water or snow thrown up by the surrounding vehicles hinders the functioning
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

2124-5. Using the driving support systems
IS350/250_U (OM53C50U)
●When driving on roads that are branching or merging
●When driving on a road surface that is wet du e to rain, previous rainfall, standing water,
etc.
●When the vehicle experiences strong up-and-down motion such as when driving on an
extremely rough road or on a seam in the pavement
●When headlight brightness at nighttime is reduced due to dirt on the lenses, or when
the headlights are misaligned
●When driving on winding roads or roads that are uneven
●When driving on rough or unpaved roads
■When changing the tires
Depending on the tires used, sufficient performance may not be maintainable.
■Warning messages for the LDA system
Warning messages are used to indicate a syst em malfunction or to inform the driver of
the need for caution while driving. ( →P. 4 76 )
CAUTION
■Before using the LDA system
Do not rely solely on the LDA system. The LDA system does not drive the vehicle auto-
matically, nor does it reduce the amount of care you need to take. As such, the driver
must always assume full responsibility fo r understanding his/her surroundings, for
operating the steering wheel to correct th e driving line, and for driving safely.
Inappropriate or negligent driving could lead to an accident.
■To avoid operating the LDA by mistake
Switch the LDA system off using the LDA switch when not in use.
■Situations unsuitable for LDA system
Do not use the LDA system in any of the following situations.
Otherwise, the system may not function correctly and could result in an accident.
●When driving with tire chains, a spare tire, or similar equipment
●When there are objects or structures along the roadside that might be misinterpreted
as lane markers (such as guardrails, a curb, reflector posts, etc.)
●When driving on snowy roads
●When pavement lane markers are difficult to see due to rain, snow, fog, sand dust, etc.
●When there are visible lines on the pavement from road repairs, or if the remains of
old lane markers are still visible on the road
●When driving on a road with lane closures due to maintenance, or when driving in a
temporary lane

2134-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
NOTICE
■To prevent damage to or incorrect operation of the LDA system
●Do not modify the headlights or attach stickers to the surface of the lights.
●Do not modify the suspension or replace it with non-genuine parts.
●Do not install or place anything on the hood or the grille. Also, do not install a grille
guard (bull bars, kangaroo bar etc.).
●If your windshield needs repairs, contact your Lexus dealer.
■Camera sensor
Observe the following to ensure that the LDA system functions correctly.
●Keep the windshield clean at all times.
Performance could be affected if the windshie ld is dirty, or if raindrops, condensation
or ice are adhering to the windshield.
●Do not spill liquid onto the camera sensor
●Do not attach window tinting to the windshield.
●Do not install an antenna in front of the camera lens.
●If the windshield is fogged up, use the windshield defogger to remove fog from the
windshield.
When it is cold, using the he ater with air blowing to the feet may allow the upper part
of the windshield to fog up. This will have a negative effect on the images.
●Do not scratch the camera lens, or let it get dirty.
When cleaning the inside of the windshield, be careful not to get any glass cleaner
etc. on the lens. Also, do not touch the lens.
For lens repair, contact your Lexus dealer.
●Do not change the installation position or di rection of the camera sensor or remove it.
The direction of the camera sensor is precisely adjusted.
●Do not subject the camera sensor to strong impact or force, and do not disassemble
the camera sensor.
●Do not replace windshield with non-genuine windshield.
Contact your Lexus dealer.
●Do not attach a sticker or other items to the
windshield near the camera sensor.

2194-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
■Sensor detection information
●The sensor’s detection areas are limited to the areas around the vehicle’s front corner
and rear bumpers.
●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 . (Wiping the sensors will resolve this prob-
lem.)
• The sensor is frozen. (Thawing th e area will resolve this problem.)
In especially cold weather, if a sensor is frozen the screen may show an abnormal
display, or obstacles may not be detected.
• The sensor is covered in any way.
• The vehicle is leaning co nsiderably 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.
• The area directly under the bumpers is not detected.
• If obstacles draw too close to the sensor.
• A non-genuine Lexus suspension (lowered suspension etc.) is installed.
• People may not be detected if they are wearing certain types of clothing.
In addition to the examples above, there are instances in which, because of their shape,
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 particular
attention to the following obstacles:
• Wires, fences, ropes, etc.
• Cotton, snow and other materials that absorb sound waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your vehi-
cle
●The following situations may occur during use.
• Depending on the shape of the obstacle and other factors, the detection distance may shorten, or detect ion may be impossible.
• Obstacles may not be detected if they are too close to the sensor.
• There will be a short delay between obst acle detection and display. Even at slow
speeds, there is a possibility that the obstacl e will come within the sensor’s detection
areas before the display is shown and the warning beep sounds.
• Thin posts or objects lower than the sensor may not be detected when approached, even if they have been detected once.
• It might be difficult to hear beeps due to the volume of the audio system or air flow noise of the air conditioning system.

2204-5. Using the driving support systems
IS350/250_U (OM53C50U)
■If a message is displayed on the multi-information display
→ P. 4 74
■Certification
XFor vehicles sold in the U.S.A.
This device complies with Part 15 of the FCC Rules. Operation is subject to the following
two conditions; (1) This device may not cause harmful interference, and (2) this device
must accept any interference received, including interference that may cause undesired
operation.
XFor vehicles sold in Canada
This ISM device complies with Canadian ICES-001.
Cet appareil ISM est conforme a la norme NMB-001 du Canada.
CAUTION
■When using the intuitive parking assist
Observe the following precautions.
Failing to do so may result in the vehicle being unable to be driv en safely and possibly
cause an accident.
●Do not use the sensor at speeds in excess of 6 mph (10 km/h).
●The sensors’ detection areas and reaction times are limited. When moving forward or
reversing, check the areas surrounding the vehicle (especially the sides of the vehi-
cle) for safety, and drive slowly, using the brake to control the vehicle’s speed.
●Do not install accessories within the sensors’ detection areas.
NOTICE
■When using intuitive parking assist
In the following situations, the system may not function correctly due to a sensor mal-
function etc. Have the vehicle checked by your Lexus dealer.
●The intuitive parking assist operation display flashes, and a beep sounds when no
obstacles are detected.
●If the area around a sensor collides with so mething, or is subjected to strong impact.
●If the bumper or grille collides with something.
●If the display shows continuously withou t beeping, except when the buzzer mute
switch has been turned on.
●If a display error occurs, first check the sensor.
If the error occurs even when there is no ice, snow or mud on the sensor, it is likely that
the sensor is malfunctioning.
■Notes when washing the vehicle
Do not apply intensive bursts of water or steam to the sensor area.
Doing so may result in the sensor malfunctioning.

2254-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
■Parking operation
When parking in a space which is in the reverse direction to the space
described in the procedure below, the steering directions will be reversed.Shift the shift position to R posi-
tion.
Turn the steering wheel so that
the estimated course lines are
within the parking space, and
back up slowly.Pa r k i n g s p a c e
Estimated course lines
When the rear position of the
vehicle has entered the parking
space, turn the steering wheel so
that the vehicle width guide lines
are within the left and right divid-
ing lines of the parking space. Vehicle width guide line
Once the vehicle width guide lines and the parking space lines are parallel,
straighten the steering wheel and back up slowly until the vehicle has com-
pletely entered the parking space.
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2274-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
■Parking operation
When parking in a space which is in the reverse direction to the space
described in the procedure below, the steering directions will be reversed.Shift the shift position to R position.
Back up until the parking assist
guide line meets the edge of the
left-hand dividing line of the park-
ing space.Parking assist guide line
Parking space dividing line
Turn the steering wheel all the way to the right, and back up slowly.
Once the vehicle is parallel with the parking space, straighten the steering
wheel and back up slowly until the vehicle has completely entered the
parking space.
Stop the vehicle in an appropriate place, and finish parking.
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2404-5. Using the driving support systems
IS350/250_U (OM53C50U)
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the
brakes are applied while driving on a slippery road surface
◆Brake assist
Generates an increased level of braking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Prevents the vehicle from rolling backward when starting on an incline or slip-
pery slope
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle speed
and steering wheel movement
Driving assist systems
To help enhance driving safety and performance, the following systems oper-
ate automatically in response to various driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too
heavily when operating the vehicle.

2444-5. Using the driving support systems
IS350/250_U (OM53C50U)
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result. Should this occur, refrain from excessive steering input
or stop the vehicle and turn the engine off. The EPS system should return to normal
within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is moved to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.