2010 Lexus GS350 brake

5
When trouble arises
523
5-1. Essential information
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
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 eyelet and the cable or chain. Always use caution for 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 damage to the automatic transmission
Never tow this vehicle from the front with the rear wheels (2WD models) or four
wheels (4WD models) on the ground.
This may cause serious damage to the automatic transmission.

530
5-1. Essential information
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
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, spongy feeling, pedal almost touches
the floor

532
5-1. Essential information
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
Event data recorder
In a crash or a near car crash event
The 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
●Vehicle speed
●To what extent the accelerator pedal was depressed
●Position of the automatic 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
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 a system to record
data in a crash or a near car crash event. This is called an Event Data
Recorder (EDR).

534
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
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.
*1: Parking brake engaged warning buzzer:
P. 549
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)*1
•Low brake fluid
• Malfunction in the brake 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 light
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.

5
When trouble arises
535
5-2. Steps to take in an emergency
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
Have the vehicle inspected immediately.
Failure 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
Malfunction in:
• The emission control system;
• The electronic engine control system;
• The electronic throttle control system; or
• The automatic transmission control system.
SRS warning light
Malfunction in:
• The SRS airbag system;
• The front passenger occupant classification system; or
• The seat belt pretensioner system.
(U.S.A.)
(Canada)
ABS warning light
Malfunction in:
•The ABS; or
• The brake assist system.
(GS460)
ECB (Electronically controlled brake system) warning light
Malfunction in the electronically controlled brake system.
Electric power steering system warning light
Malfunction in the EPS.
“PCS” warning light (if equipped)
Malfunction in the pre-collision system.

540
5-2. Steps to take in an emergency
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
■If the tire pressure warning light comes on after blinking for 1 minute frequently
If the tire pressure warning light comes on after blinking for 1 minute frequently
when the “ENGINE START STOP” switch is turned to IGNITION ON mode, have
it checked by your Lexus dealer.
CAUTION
■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 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.
●Vehicles with run-flat tires:
• Decelerate to the lowest appropriate speed as soon as possible. Do not drive
over 55 mph (90 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.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.

546
5-2. Steps to take in an emergency
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
Wa r n i n g m e s s a g eDetails
(Flashing)
(If equipped)
Malfunction in the radar cruise control system.
Stop the vehicle in a safe place. Turn the “ENGINE
START STOP” switch to OFF and then to IGNITION
ON mode again to reset the cruise control system.
Malfunction in the charging system.
Malfunction in the power steering system.
Malfunction in the brake system.
Malfunction in the ABS.

5
When trouble arises
549
5-2. Steps to take in an emergency
GS_G_U (OM30C80U)
June 29, 2011 10:30 am
Wa r n i n g m e s s a g eDetailsCorrection procedure
The trunk is not fully
closed.
flashes and a
buzzer sounds to indi-
cate that trunk is not fully
closed (with the vehicle
having reached a speed
of 3 mph [5 km/h]).
Close the trunk.
(Flashing)
(If equipped)
The moon roof is not fully
closed (with the
“ENGINE START STOP”
switch is OFF and the
driver’s door opened).
Close the moon roof.
(Flashing)
The parking brake is still
engaged (with the vehicle
having reached a speed
of more than 3 mph [5
km/h]).
Release the parking
brake.
The washer fluid level is
low.Add washer fluid.
The engine oil level is low.Check the engine oil level,
and add if necessary.