brake Lexus IS250C 2010 Workshop Manual

5
When trouble arises
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5-1. Essential information
10_IS250C/350C_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 5 7 )
If they are damaged, use a towing dolly or flat bed truck.

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5-1. Essential information
10_IS250C/350C_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.
●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

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5-1. Essential information
10_IS250C/350C_U
Towing with a wheel lift-type truckFrom the front Vehicles with an automatic trans-
mission: Use a towing dolly under
the rear wheels.
Vehicles with a manual transmis-
sions: We recommend to use a
towing dolly under the rear wheels.
When not using a towing dolly,
release the parking brake and shift
the shift lever to N.
From the rearSwitch to ACCESSORY mode so
that the steering wheel is
unlocked.

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5-1. Essential information
10_IS250C/350C_U
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
●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 normal
■ Audible symptoms
●Changes in exhaust sound
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises related to the engine
■ Operational symptoms
●Engine missing, stumbling or running rough
● 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, sp ongy feeling, pedal almost touches
the floor

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5-1. Essential information
10_IS250C/350C_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.

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10_IS250C/350C_U
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer sounds...
Stop the vehicle immediately. Continuing to drive the vehicle may be dangerous.
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
*: Parking brake engaged warning buzzer
→P. 4 7 5
Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehicle
that may lead to an accident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Brake system warning light (warning buzzer)*
• Low brake fluid
• Malfunction in the brake booster system This light also comes on when the parking brake is not
released. If the light turns off after the parking brake is fully
released the system is operating normally.
Warning lightWarning light/Details
Charging system warning lightIndicates a malfunction in the vehicle’s charging system.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, but then turns off, this does not necessar-
ily indicate a malfunction in the system.

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5-2. Steps to take in an emergency
10_IS250C/350C_U
Have the vehicle inspected by your Lexus dealer immediately.Failing to investigate the cause of the following warnings may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
Warning lightWarning light/Details
(U.S.A.)
(Canada)
Malfunction indicator lamp Indicates a malfunction in:
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic automatic transmission control system.
SRS warning lightIndicates a malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system.
(U.S.A.)
(Canada)
“ABS” warning lightIndicates a malfunction in:
•The ABS;
• The brake assist system.
Electric power steering system warning lightIndicates a malfunction in the EPS (Electric Power Steering)
system.
Pre-collision system warning light (if equipped)Indicates a malfunction in the pre-collision system.

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5-2. Steps to take in an emergency
10_IS250C/350C_U
■If the open retractable hardtop warning buzzer sounds
Immediately stop the vehicle in a safe place and open or close the retractable hard-
top fully.
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.Vehicles with run-flat tires
• Decelerate to the lowest appropriate speed as soon as possible. Do not drive over 50 mph (80 km/h).
• Check and adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, it is probable that you have a flat tire. Have the tire replaced 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.
Vehicles with standard tires
• Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pressure immediately.
• If the tire pressure warning light comes on even after tire inflation pressure adjustment, 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.

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5-2. Steps to take in an emergency
10_IS250C/350C_U
The roof switch was
pressed while the lug-
gage cover was not in the
correct position.
(→ P. 8 1 )
Indicates that the parking
brake is still engaged.
flashes and a
buzzer sounds to indi-
cate that the parking
brake is still engaged
(with the vehicle having
reached a speed of 3
mph [5 km/h]).
Release the parking
brake.
Indicates that the washer
fluid level is low.Add washer fluid.
Indicates that engine oil
level is low.Check the level of engine
oil, and add if necessary.
MessageDetailsCorrection procedure

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5-2. Steps to take in an emergency
10_IS250C/350C_U
(If equipped)
Indicates that intuitive
parking assist is dirty or
covered with ice.
Clean the sensor.
(Flashing)
(If equipped)
Indicates that the radar
cruise control sensor is
dirty or covered with ice.
Clean the sensor.
(Flashing and then con- tinuously on)
(Flashing)
(If equipped)Indicates that the radar
cruise control system is
unable to judge vehicle-
to-vehicle distance.
• Switch the driving mode to either the normal or
power mode.
• If the windshield wipers are on, turn them off or
set them to either the
intermittent or the slow
mode.
(Flashing)
(If equipped)
Indicates that your vehi-
cle is nearing the vehicle
ahead (in radar cruise
mode).
Slow the vehicle by apply-
ing the brakes.
MessageDetailsCorrection procedure