brakes Lexus IS250 2012 User Guide

5
When trouble arises
463
5-1. Essential information
IS350/250_U
If your vehicle needs to be towed
Before towingThe following may indicate a problem with your transmission. Contact
your Lexus dealer before towing.
● The engine is running, but the vehicle will not move.
● The vehicle makes an abnormal sound.
Emergency towing
If a tow truck is not available, in an emergency your vehicle may be tem-
porarily towed using a cable or chain secured to the emergency towing
eyelet(s). This should only be attempted on hard, surfaced roads for short
distances at low speeds.
A driver must be in the vehicle to steer and operate the brakes. The vehi-
cle’s wheels, drive train, axles, steering and brakes must be in good condi-
tion. Towing eyelets
If towing is necessary, we recommend having your vehicle towed by your
Lexus dealer or a commercial towing se rvice, using a lift-type truck or a flat
bed truck.
Use a safety chain system for all towing, and abide by all state/provincial
and local laws.
If towing from the rear, the vehicle’s front wheels and axles must be in good
condition. ( →P. 4 6 7 )
If they are damaged, use a towing dolly or flat bed truck.

464
5-1. Essential information
IS350/250_U
■Emergency towing procedureRelease the parking brake.
Shift the shift lever to N.
Put the “ENGINE START STOP” switch in ACCESSORY mode or IGNI-
TION ON mode.
CAUTION
■Caution while towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelets and the cables or chains. Always be cautious of the
surroundings and other vehicles 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.
NOTICE
■To prevent causing serious da mage to the transmission
(vehicles with an automatic transmission)
Never tow this vehicle from the front with the rear wheels on the ground.
This may cause serious damage to the transmission.
■When towing a vehicle without using a towing dolly
(vehicles with a manual transmission)
The “ENGINE START STOP” switch must not be OFF.
STEP1
STEP2
STEP3

478
5-2. Steps to take in an emergency
IS350/250_U
CAUTION
■When the electric power steering warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, firmly hold and
operate it using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pres-
sure immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If the tire is flat,
change to the spare tire and have the flat tire repaired by the nearest Lexus
dealer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could
lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.

490
5-2. Steps to take in an emergency
IS350/250_U
Once
(Vehicles with an auto-matic transmission)
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSORY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while applying the
brakes.
Once
(Vehicles with a manual
transmission)
Indicates that a
door has been
opened or closed
and the “ENGINE
START STOP”
switch has been
switched twice to
ACCESSORY
mode from OFF.
Press the
“ENGINE START
STOP” switch
while depressing
the clutch pedal.

(Flashing)
Indicates that the
steering lock has
not released
within 3 seconds
of pressing the
“ENGINE START
STOP” switch.Press the
“ENGINE START
STOP” switch
again while turn-
ing the steering
wheel with the
brake pedal
depressed.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection
procedure

5
When trouble arises
507
5-2. Steps to take in an emergency
IS350/250_U
Changing “ENGINE START STOP” switch modes and starting the engine
Automatic transmissionShift the shift lever to P and apply the brakes.
Touch the Lexus emblem side of
the electronic key to the
“ENGINE START STOP” switch.
An alarm will sound to indicate that
the start function cannot detect the
electronic key that is touched to
the “ENGINE START STOP”
switch if any of the doors is opened
and closed while the key is touched
to the switch.
To change “ENGINE START STOP” switch modes: Within 10
seconds of the buzzer sounding, release the brake pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the switch is pressed.
(→P. 141)
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds after the buzzer sounds, keeping the brake
pedal depressed.
STEP1
STEP2
STEP3

518
5-2. Steps to take in an emergency
IS350/250_U
If your vehicle has to be stopped in an emergency
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
possible before turning off the engine.
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:
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.
If the shift lever is shifted to N After slowing down, stop the vehicle in a safe place by the road.
Stop the engine.
If the shift lever cannot be shifted to N Keep depressing the brake pedal with both feet to reduce vehi-
cle speed as much as possible.
Stop the engine by pressing and
holding the “ENGINE START
STOP” switch for 3 consecutive
seconds or more.
Stop the vehicle in a safe place by the road.
STEP1
STEP2
STEP3
STEP4
STEP3
Press and hold for 3 seconds or more
STEP4
STEP5

530
6-1. Specifications
IS350/250_U
Clutch
Brakes
*1: Minimum pedal clearance when depressed with a force of 110 lbf (490 N, 50
kgf) while the engine is running.
*2: Parking brake pedal travel when depressed with a force of 67.4 lbf (300 N,30.6 kgf).
*3: Parking brake lever travel when pulled up with a force of 45.0 lbf (200 N, 20.4kgf).
Clutch free play0.2  0.6 in. (5  15 mm)
Fluid typeSAE J1703 or FMVSS No.116 DOT 3
Pe d a l c l e a r a n c e *1
IS 350
IS 250
Manual transmission
Automatic transmission4.13 in. (105 mm) Min.
4.09 in. (104 mm) Min.
4.3 in. (108 mm) Min.
Pedal free play0.04  0.08 in. (1.0  2.0 mm)
Brake pad wear limit0.04 in. (1.0 mm)
Parking brake lining wear limit0.04 in. (1.0 mm)
Parking brake pedal travel *2/
lever travel
*3
Pedal type
Lever type7  9 clicks
5
 7 clicks
Fluid typeSAE J1703 or FMVSS No. 116 DOT 3

546
6-1. Specifications
IS350/250_U■
Temperature A, B, C
The temperature grades are A (the highest), B, and C, representing
the tire's resistance to the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a specified indoor
laboratory test wheel.
Sustained high temperature can cause the material of the tire to degenerate
and reduce tire life, and excessive temperature can lead to sudden tire fail-
ure.
The grade C corresponds to a level of performance which all passenger car
tires must meet under the Federal Motor Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
Glossary of tire terminology
Tire related termMeaning
Accessory weight
The combined weight (in excess of those standard
items which may be replaced) of automatic transmis-
sion, power steering, power brakes, power windows,
power seats, radio and heater, to the extent that these
items are available as factory-installed equipment
(whether installed or not)
Cold tire inflation pres-
sureTire pressure when the vehicle has been parked for
three hours or more, or has not been driven more
than 1 mile or 1.5 km under that condition
Curb weight
The weight of a motor vehicle with standard equip-
ment, including the maximum capacity of fuel, oil and
coolant, and if so equipped, air conditioning and
additional weight optional engine

547
6-1. Specifications
6
Vehicle specifications
IS350/250_U
Maximum inflation pres-
sureThe maximum cold inflated pressure to which a tire
may be inflated, shown on the sidewall of the tire
Maximum loaded vehicle
weight
The sum of:
(a) Curb weight
(b) Accessory weight
(c) Vehicle capacity weight
(d) Production options weight
Normal occupant weight150 lb. (68 kg) times the number of occupants speci-
fied in the second column of Table 1
* that follows
Production options
weight
The combined weight of installed regular production
options weighing over 5 lb. (2.3 kg) in excess of the
standard items which they replace, not previously
considered in curb weight or accessory weight,
including heavy duty brakes, ride levelers, roof rack,
heavy duty battery, and special trim
Vehicle capacity weight
(Total load capacity)The rated cargo and luggage load plus 150 lb. (68
kg) times the vehicle's designated seating capacity
Occupant distributionDistribution of occupants in a vehicle as specified in
the third column of Table 1
* below
Recommended inflation
pressureCold tire inflation pressure recommended by a man-
ufacturer.
RimA metal support for a tire or a tire and tube assembly
upon which the tire beads are seated
Rim diameter
(Wheel diameter)Nominal diameter of the bead seat
Rim size designationRim diameter and width
Rim type designationThe industry manufacturer's designation for a rim by
style or code
Tire related termMeaning