brake Lexus IS250 2014 Service Manual

2774-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
CAUTION
■Limitations of the pre-crash safety system
Do not overly rely on the pre-crash safety system. Always drive safely, taking care to
observe your surroundings and checking for any obstacles or other road hazards.
Failure to do so may cause an accident resulting in death or serious injury.
■Handling the radar sensor
Observe the following to ensure the pre-crash safety system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
●Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover 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 sen-
sor or surrounding area is subject to a strong impact, always have the area inspected
and adjusted by any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.
■Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-crash safety system is intended to assist
the driver in avoiding collisions through the process of LOOK-JUDGE-ACT. There are
limits to the degree of assistance the system can provide, so please keep in mind the
following important points.
●Assisting the driver in watching the road
The pre-crash safety system is only able to detect obstacles directly in front of the
vehicle, and only within a limited range. It is not a mechanism that allows careless or
inattentive driving, and it is not a system that can assist the driver in low-visibility con-
ditions. It is still necessary for the driver to pay close attention to the vehicle’s sur-
roundings.
●Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data available to
the pre-crash safety system is that from obstacles it has detected directly in front of
the vehicle. Therefore, it is absolutely necessary for the driver to remain vigilant and
to determine whether or not there is a possibility of collision in any given situation.
●Assisting the driver in taking action
The pre-crash safety system’s braking assist feature is designed to help reduce the
severity of a collision, and so only acts when the system has judged that a collision is
unavoidable. This system by itself is not capable of automatically avoiding a collision
or bringing the vehicle to a stop safely. For this reason, when encountering a danger-
ous situation the driver must take direct and immediate action in order to ensure the
safety of all involved.

288
IS250_EE(OM53C51E)4-6. Driving tips
●Use fluids that are appropriate to the prevailing outside temperatures.
•Engine oil
• Engine coolant
•Washer fluid
●Have a service technician inspect the condition of the battery.
●Have the vehicle fitted with four snow tires or purchase a set of tire chains for
the rear tires.
*
Ensure that all tires are the specified size and brand, and that chains match the size
of the tires.
*: Tire chains cannot be mounted on the 18-inch tires.
Perform the following according to the driving conditions:
●Do not try to forcibly open a window or move a wiper that is frozen. Pour
warm water over the frozen area to melt the ice. Wipe away the water imme-
diately to prevent it from freezing.
●To ensure proper operation of the climate control system fan, remove any
snow that has accumulated on the air inlet vents in front of the windshield.
●Check for and remove any excess ice or snow that may have accumulated on
the exterior lights, vehicle’s roof, chassis, around the tires or on the brakes.
●Remove any snow or mud from the bottom of your shoes before getting in the
vehicle.
Accelerate the vehicle slowly, keep a safe distance between you and the vehicle
ahead, and drive at a reduced speed suitable to road conditions.
Winter driving tips
Carry out the necessary preparations and inspections before driving the vehi-
cle in winter. Always drive the vehicle in a manner appropriate to the prevail-
ing weather conditions.
Preparation for winter
Before driving the vehicle
When driving the vehicle

2894-6. Driving tips
4
Driving
IS250_EE(OM53C51E)
Park the vehicle and move the shift lever to P without setting the parking brake.
The parking brake may freeze up, preventing it from being released. If necessary,
block the wheels to prevent inadvertent sliding or creeping.
XExcept vehicles with 18-inch tires
Use the correct tire chain size when mounting the tire chains.
Chain size is regulated for each tire size.
Side chain
(3 mm [0.12 in.] in diameter)
Cross chain
(4 mm [0.16 in.] in diameter)
XVehicles with 18-inch tires
Tire chains cannot be mounted on the 18-inch tires.
Snow tires should be used instead.
Regulations regarding the use of tire chains vary depending on location and type
of road. Always check local regulations before installing chains.
■Tire chain installation
Observe the following precautions when installing and removing chains:
●Install and remove tire chains in a safe location.
●Install tire chains on the rear tires. Do not install tire chains on the front tires.
●Install tire chains on rear tires as tightly as possible. Retighten chains after driving 0.5
 1.0 km (1 /4  1 /2 mile).
●Install tire chains following the instructions provided with the tire chains.
When parking the vehicle
Selecting tire chains
1
2
Regulations on the use of tire chains

4127-2. Maintenance
IS250_EE(OM53C51E)
■Where to go for maintenance service?
In order to maintain your vehicle in the best possible condition, Lexus recommends that
maintenance service operations as well as other inspections and repairs be carried out
by authorized Lexus dealers or repairers or other duly qualified and equipped profes-
sionals. For repairs and services covered by your warranty, please visit an authorized
Lexus dealer or repairer, who will use genuine Lexus parts in repairing any difficulties you
may encounter. There can also be advantages in utilizing authorized Lexus dealers or
repairers for non-warranty repairs and services, as members of the Lexus network will be
able to expertly assist you with any difficulties you may encounter.
Your Lexus dealer or repairer, or another duly qualified and equipped professional will
perform all of the scheduled maintenance on your vehicle reliably and economically due
to their experience with Lexus vehicles.
■Does your vehicle need repairs?
Be on the alert for changes in performance and sounds, and visual tip-offs that indicate
service is needed. Some important clues are:
●Engine missing, stumbling or pinging
●Appreciable loss of power
●Strange engine noises
●A fluid leak under the vehicle (However, water dripping from the air conditioning sys-
tem after use is normal.)
●Change in exhaust sound (This may indicate a dangerous carbon monoxide leak. Drive
with the windows open and have the exhaust system checked immediately.)
●Flat-looking tires, excessive tire squeal when cornering, uneven tire wear
●Vehicle pulls to one side when driven straight on a level road
●Strange noises related to suspension movement
●Loss of brake effectiveness, spongy feeling brake pedal, pedal almost touches the floor,
vehicle pulls to one side when braking
●Engine coolant temperature continually higher than normal (→P. 9 5 )
If you notice any of these clues, take your vehicle to any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional as soon as possible. Your
vehicle may need adjustment or repair.
CAUTION
■If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and possible
death or serious injury.
■Handling of the battery
Battery posts, terminals and related accessories contain lead and lead compounds
which are known to cause brain damage. Wash your hands after handling. (→P. 4 2 2 )

4147-3. Do-it-yourself maintenance
IS250_EE(OM53C51E)
CAUTION
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energized. To avoid death or serious injury, observe
the following precautions.
■When working on the engine compartment
●Keep hands, clothing and tools away from the moving fan and engine drive belt.
●Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driving
as they may be hot. Oil and other fluids may also be hot.
●Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment.
●Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel and
battery fumes are flammable.
●Be extremely cautious when working on the battery. It contains poisonous and corro-
sive sulfuric acid.
●Take care because brake fluid can harm your hands or eyes and damage painted sur-
faces. If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, consult a doctor.
■When working near the electric cooling fans or radiator grille
Be sure the engine switch is off.
With the engine switch in IGNITION ON mode, the electric cooling fans may auto-
matically start to run if the air conditioning is on and/or the coolant temperature is high.
(→P. 4 2 2 )
■Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc. from getting in
your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to dirt
in the air.
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads wear or when
the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, it may indicate a serious problem.

4678-1. Essential information
8
When trouble arises
IS250_EE(OM53C51E)
Steadily step on the brake pedal with both feet and firmly depress it.
Do not pump the brake pedal repeatedly as this will increase the effort required to
slow the vehicle.
Shift the shift lever to N.
XIf the shift lever is shifted to N
After slowing down, stop the vehicle in a safe place by the road.
Stop the engine.
XIf the shift lever cannot be shifted to N
Keep depressing the brake pedal with both feet to reduce vehicle speed as
much as possible.
To stop the engine, press and hold
the engine switch for 2 consecutive
seconds or more, or press it briefly 3
times or more in succession.
Stop the vehicle in a safe place by the road.
If your vehicle has to be stopped in an emergency
Only in an emergency, such as if it becomes impossible to stop the vehicle in
the normal way, stop the vehicle using the following procedure:
1
2
3
4
3
Press and hold for 2 seconds or more
or press briefly 3 times or more
4
CAUTION
■If the engine has to be turned off while driving
Power assist for the brakes and steering wheel will be lost, making the brake pedal
harder to depress and the steering wheel heavier to turn. Decelerate as much as possi-
ble before turning off the engine.
5

4708-2. Steps to take in an emergency
IS250_EE(OM53C51E)
If your Lexus is transported by a flatbed
truck, it should be tied down at the
locations shown in the illustration.
If you use chains or cables to tie down
your vehicle, the angles shaded in black
must be 45°.
Do not overly tighten the tie downs or
the vehicle may be damaged.
If a tow truck is not available in an emergency, your vehicle may be temporarily
towed using a cable or chain secured to the emergency towing eyelet. This
should only be attempted on hard surfaced roads for 80 km (50 miles) at low
speeds.
A driver must be in the vehicle to steer and operate the brakes. The vehicle’s
wheels, drive train, axles, steering and brakes must be in good condition.
Using a flatbed truck
Emergency towing

4718-2. Steps to take in an emergency
8
When trouble arises
IS250_EE(OM53C51E)
Take out the towing eyelet. (→P. 4 9 7 , 5 0 8 )
Remove the eyelet cover using a flat-
head screwdriver.
To protect the bodywork, place a rag
between the screwdriver and the vehi-
cle body as shown in the illustration.
Insert the towing eyelet into the hole
and tighten partially by hand.
Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
Securely attach a cable or chain to the towing eyelet.
Take care not to damage the vehicle body.
Enter the vehicle being towed and start the engine.
If the engine does not start, turn the engine switch to IGNITION ON mode.
Shift the shift position to N and release the parking brake.
When the shift lever cannot be shifted: →P. 5 2 3
Emergency towing procedure
1
2
3
4
5
6
7

4728-2. Steps to take in an emergency
IS250_EE(OM53C51E)
■While towing
If the engine is not running, the power assist for the brakes and steering will not function,
making steering and braking more difficult.
■Wheel nut wrench
Wheel nut wrench is installed in luggage compartment. (→P. 4 9 7 , 5 0 8 )
CAUTION
Observe the following precautions.
Failure to do so may result in death or serious injury.
■When towing the vehicle
■While towing
●When towing using cables or chains, avoid sudden starts, etc. which place excessive
stress on the towing eyelet, cables or chains.
The towing eyelet, cables or chains may become damaged, broken debris may hit
people and cause serious damage.
●Do not turn the engine switch off.
There is a possibility that the steering wheel is locked and cannot be operated.
■Installing towing eyelet to the vehicle
Make sure that towing eyelet is installed securely.
If not securely installed, towing eyelet may come loose during towing.
Be sure to transport the vehicle with all four
wheels raised off the ground. If the vehicle is
towed with the tires contacting the ground, the
drivetrain and related parts may be damaged
or an accident may occur due to a change in
direction of the vehicle.

4748-2. Steps to take in an emergency
IS250_EE(OM53C51E)
●Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher than nor-
mal.
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the engine
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy feeling, pedal almost touches the floor
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional as soon as possible.
Visible s ymp toms
Audible symptoms
Operational symptoms