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736
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7-2. Steps to take in an emergency
If you think something is wrong
●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.
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the hybrid system
●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 notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Lexus dealer as soon as pos-
sible.
Visible symptoms
Audible symptoms
Operational symptoms
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7
When trouble arises
7-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds
The following warning indicates a possible problem in the brake system.
Immediately stop the vehicle in a safe place and contact your Lexus
dealer.
Calmly perform the following actions if any of the warning lights comes
on or flashes. If a light comes on or flashes, but then goes off, this does
not necessarily indicate a malfunction in the system. However, if this
continues to occur, have the vehicle inspected by your Lexus dealer.
Stop the vehicle immediately. Continuing to drive the vehicle may
be dangerous.
Warning lightWarning light/Details
(U.S.A.)
(Canada)Brake system warning light (warning buzzer) • Low brake fluid
• Malfunction in the electronically controlled brake system
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7387-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)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.
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.
Stop the vehicle immediately.
Warning lightWarning light/Details
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
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 hybrid system;
• The electronic engine control system;
• The electronic throttle control system; or
• The electronic hybrid transmission control system
SRS warning lightIndicates a 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 Indicates a malfunction in:
•The ABS; or
• The brake assist system
Electric power steering system warning light (warning buzzer)Indicates a malfunction in the EPS (Electric Power Steering)
system
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7397-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
(Flashes)
(If equipped)
Pre-collision system warning light Indicates a malfunction in the pre-collision system
The warning light will operate as follows, even when the system
is not malfunctioning:
• The light will flash quickly when the system is operating. (→ P. 3 1 5 )
• The light will turn on when the pre-collision system is dis- abled. ( →P. 3 1 6 )
• The light will flash when the system cannot temporarily be used. ( →P. 76 1 )
Slip indicator
Indicates a malfunction in:
• The VSC system; or
•The TRAC system
The light will flash when the VSC or the TRAC system is operat-
ing.
(Flashes)
(If equipped)
“A F S O F F ” i n d i c a t o r Indicates a malfunction in the adaptive front-lighting system
(Flashes)
Brake hold operated indicatorIndicates a malfunction in the brake hold system
(Flashes)(U.S.A.)
(Flashes)
(Canada)
Parking brake indicator Indicates a malfunction in the parking brake system
Warning lightWarning light/Details
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7407-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)After taking the specified steps to correct the suspected problem, check
that the warning light goes off.
Brake system warning light
Indicates a malfunction in:
• The electronically controlled brake system;
• The regenerative braking system; or
• The parking brake system
Follow the correction procedures.
Warning lightWarning light/Details
Warning lightWarning light/DetailsCorrection procedure
Open door warning light
(warning buzzer)
*1
Indicates that a door or the
trunk is not fully closed
Check that all the doors and
the trunk are closed.
Low fuel level warning lightIndicates remaining fuel is
approximately 2.6 gal. (10.0
L, 2.2 Imp.gal.) or less
Refuel the vehicle.
Seat belt reminder light (warn-
ing buzzer)
*2
Warns the driver and/or front
passenger to fasten their seat
belts
Fasten the seat belt.If the front passenger’s seat is
occupied, the front passen-
ger’s seat belt also needs to
be fastened to make the
warning light (warning
buzzer) off.
Master warning lightA buzzer sounds and the
warning light comes on and
flashes to indicate that the
master warning system has
detected a malfunction.
→ P. 74 7
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7417-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
*1: Open door warning buzzer:→ P. 7 5 4
*2: Driver’s seat belt buzzer:
The driver’s seat belt buzzer sounds to alert the driver that his or her seat belt is
not fastened. Once the power switch is turned to ON mode, the buzzer sounds
for 6 seconds. If the vehicle reaches a speed of 12 mph (20 km/h), the buzzer
sounds once. If the seat belt is still unfastened after 24 seconds, the buzzer will
sound intermittently for 10 seconds. Then, if the seat belt is still unfastened, the
buzzer will sound in a different tone for 20 more seconds.
Front passenger’s seat belt buzzer:
The front passenger’s seat belt buzzer sounds to alert the front passenger that his
or her seat belt is not fastened. The buzzer sounds once if the vehicle reaches a
speed of 12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seconds. Then, if the seat belt is still unfas-
tened, the buzzer will sound in a different tone for 20 more seconds.
Tire pressure warning light
When the light comes on:
Low tire inflation pressure such
as • Natural causes ( →P. 74 3 )
• Flat tire ( →P. 7 7 5 )
Adjust the tire inflation pressure
to the specified level.
The light will turn off after a
few minutes. In case the light
does not turn off even if the
tire inflation pressure is
adjusted, have the system
checked by your Lexus
dealer.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pressure
warning system
Have the system checked by
your Lexus dealer.
Warning lightWarning light/DetailsCorrection procedure
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7427-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors,
side impact sensors (front door), side impact sensors (front), side impact sensors
(rear), driver’s seat position sensor, driver’s seat belt buckle switch, front passenger
occupant classification system, “AIR BAG ON” indicator light, “AIR BAG OFF” indi-
cator light, front passenger’s seat belt buckle switch, seat belt pretensioner assem-
blies, airbags, interconnecting wiring and power sources. (→P. 4 0 )
■Front passenger detection sensor, seat belt reminder and warning buzzer
If luggage is placed on the front passenger seat, the front passenger detection sen-
sor may cause the warning light to flash and the warning buzzer to sound even if a
passenger is not sitting in the seat.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
■Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage temporarily
drops, the electric power steering system warning light may come on and the warn-
ing buzzer may sound.
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Pushing the tire
pressure warning reset switch will not turn off the tire pressure warning light.
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7437-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural
air leaks and tire inflation pressure changes caused by temperature. In this case,
adjusting the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with a tire pressure warning valve and trans-
mitter. If a tire goes flat, the tire pressure warning light will not turn off even though
the flat tire has been replaced with the spare tire.
■Conditions that the tire pressure warning system may not function properly
→P. 6 8 3
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when
the power switch is turned to ON mode, have it checked by your Lexus dealer.
■Warning buzzer
In some cases, the buzzer may not be heard because of noisy place or an audio
sound.
■Customization
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features: → P. 8 3 3 )
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