2015 Lexus IS250 steering

1614-2. Driving procedures
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Driving
IS350/250_U (OM53C50U)
■Auto power off function
If the vehicle is left in ACCESSORY mode for more than 20 minutes or IGNITION ON
mode (the engine is not running) for more than an hour with the shift lever in P, the engine
switch will automatically turn off. However, this function cannot entirely prevent battery
discharge. Do not leave the vehicle with the engine switch in ACCESSORY or IGNI-
TION ON mode for long periods of ti me when the engine is not running.
■Electronic key battery depletion
P. 1 0 1
■Conditions affe cting operation
 P. 116
■Notes for the entry function
P. 117
■If the engine does not start
●Check that the shift lever is securely set in P. The engine may not start if the shift lever is
displaced out of P.
●The engine immobilizer system may not have been deactivated. ( P. 6 9 )
Contact your Lexus dealer.
■Steering lock
After turning the engine switch off and opening and closing the doors, the steering wheel
will be locked due to the stee ring lock function. Operating the engine switch again auto-
matically cancels the steering lock.
■When the steering lock cannot be released
■Steering lock motor overheating prevention
To prevent the steering lock motor from over heating, operation of the motor may be sus-
pended if the engine is turned on and off repeat edly in a short period of time. In this case,
refrain from operating the engine switch. After about 10 seconds, the steering lock
motor will resume functioning. “Steering Lock active” will be displayed on the
multi-information display.
Check that the shift lever is in P. Press the
engine switch while turning the steering wheel
left and right.

1624-2. Driving procedures
IS350/250_U (OM53C50U)
■When “Check Access System with Elec. Key” is displayed on the multi-information dis-
play
The system may be malfunctioning. Have the vehicle inspected by your Lexus dealer
immediately.
■If the electronic key battery is depleted
 P. 4 3 9
■Operation of the engine switch
●When operating the engine switch, one short, firm press is enough. If the switch is
pressed improperly, the engine may not start or the engine switch mode may not
change. It is not necessary to press and hold the switch.
●If attempting to restart the engine immediat ely after turning the engine switch off, the
engine may not start in some cases. After tu rning the engine switch off, please wait a
few seconds before re starting the engine.
■If the smart access system with push-butto n start has been deactivated by a customized
setting
 P. 4 9 9
CAUTION
■When starting the engine
Always start the engine while sitting in the driver’s seat. Do not depress the accelerator
pedal while starting the engine under any circumstances.
Doing so may cause an accident resu lting in death or serious injury.
■Caution while driving
If engine failure occurs while the vehicle is moving, do not lock or open the doors until
the vehicle reaches a safe and complete stop. Activation of the steering lock in this cir-
cumstance may lead to an accident, re sulting in death or serious injury.
■Stopping the engine in an emergency
If you want to stop the engine in an emergency while driving the vehicle, press and hold
the engine switch for more than 2 seconds, or press it briefly 3 times or more in succes-
sion. ( P. 4 5 7 )
However, do not touch the engine switch while driving except in an emergency. Turning
the engine off while driving will not cause lo ss of steering or braking control, but the
power assist to these systems will be lost. Th is will make it more difficult to steer and
brake, so you should pull over and stop the vehicle as soon as it is safe to do so.

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 thos e covered with rain, ice or snow
●On steep downhills, or where there are sudden 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 vehicle-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 for understanding his/her surroundings, for
operating the steering wheel to correct the driving line, and for driving safely.
Inappropriate or negligent drivin g 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

2224-5. Using the driving support systems
IS350/250_U (OM53C50U)
■Using the system
Use any of the following modes.
●Estimated course line display mode ( P. 2 2 4 )
Estimated course lines are dis-
played which move in accor-
dance with the operation of the
steering wheel.
●Parking assist guide line display mode ( P. 2 2 6 )
The steering wheel return points
(parking assist guide lines) are
displayed.
●Distance guide line display mode
Distance guide lines only are dis-
played.

2244-5. Using the driving support systems
IS350/250_U (OM53C50U)
■Screen description
Estimated course line display mode
Vehicle center guide line
The line indicates the estimated vehicle center on the ground.
Vehicle width guide line
The line indicates a guide path when the vehicle is being backed straight up.
The displayed width is wider than the actual vehicle width.
The line aligns with the estimated course lines when the steering wheel is straight.
Estimated course lines
The lines show an estimated course when the steering wheel is turned.
Distance guide line
The line moves, together with the estimated course lines, in sync with the steering
wheel. The line shows points approximately 1.5 ft. (0.5 m) (red) and approximately
3 ft. (1 m) (yellow) from the center of the edge of the bumper.
Distance guide line
The line shows distance behind the vehicl e, a point approximately 1.5 ft. (0.5 m)
(blue) from the edge of the bumper.
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2254-5. Using the driving support systems
4
Driving
IS350/250_U (OM53C50U)
■Pa r k i n g o p e ra t i o n
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.Parking space
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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2264-5. Using the driving support systems
IS350/250_U (OM53C50U)
Stop the vehicle in an appropri ate place, and finish parking.
■Screen description
Parking assist guide line display mode
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Vehicle width guide lines
These lines indicate a guide path when the vehicle is being backed straight
up. The displayed width is wider than the actual vehicle width.
Parking assist guide lines
These lines indicate the path of the smallest turn possible behind the vehi-
cle.
These lines also indicate the approx imate position of the steering wheel
when parking.
Distance guide line
This line (red) indicates points approxim ately 1.5 ft. (0.5 m) behind the rear
bumper of your vehicle.
Vehicle center guide line
The line indicates the estimated vehicle center on the ground.1
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