Page 692 of 825

5
When trouble arises
691
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
*1: Open door warning buzzer:
The open door warning buzzer sounds to alert one or more of the doors is not
fully closed (with the vehicle having reached a speed of 3 mph [5 km/h]).
( P. 7 0 3 )
*2: Driver’s and front passenger’s seat belt reminder buzzer:
The driver’s and front passenger’s seat belts reminder buzzer sounds to alert
the driver and front passenger that his/he r seat belt is not fastened. Once the
“ENGINE START STOP” switch is turned to IGNITION ON mode, the buzzer
sounds for 4 to 8 seconds. If the vehicl e reaches a speed of 12 mph (20 km/h),
the buzzer sounds intermittently for 10 se conds. Then, if the seat belt is still
unfastened, the buzzer w ill sound in a different tone for 20 more seconds.
Warning lightWarning light/DetailsCorrection procedure
Master warning light
A buzzer sounds and the
warning light comes on and
flashes to indicate that the
master warning system has
detected a malfunction.
P. 6 9 8
Tire pressure warning light
When the light comes on:
Low tire inflation pressure.Adjust the tire inflation pres-
sure.
When the light comes on after
blinking for 1 minute:
Malfunction in the tire pres-
sure warning system.
Have the system checked by
your Lexus dealer.
Page 693 of 825

692
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
■SRS warning light
This warning light system monitors the airbag sensor assembly, front airbag sensors,
side and curtain shield airbag sensors, rear side and curtain shield airbag sensors,
floor sensor, driver’s seat belt buckle switch, front passenger occupant classification
system, “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front pas-
senger’s seat belt buckle switch, seat belt pretensioner assemblies, inflators, inter-
connecting wiring and power sources. ( P. 121)
■Front passenger detection sensor and passenger seat belt reminder
●If luggage is placed on the front passenger seat, the front passenger detection
sensor may cause the warning light to flash, even if a passenger is not sitting in
the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the
warning light may not operate properly.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Lexus dealer as soon
as possible.
Page 694 of 825

5
When trouble arises
693
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
■When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The spare tire is also equipped with the tire pressure warning valve and transmitter.
The tire pressure warning light will turn on if the tire inflation pressure of the spare
tire is low. If a tire goes flat, even though the flat tire is replaced with the spare tire,
the tire pressure warning light does not turn off. Replace the spare tire with the
repaired tire and adjust the proper tire inflation pressure. The tire pressure warning
light will turn off after a few minutes.
■If the tire pressure warning system is inoperative
The tire pressure warning system will be come inoperative in the following condi-
tions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmitters are used.
●If the ID code on the tire pressure warning valves and transmitters is not regis-
tered in the tire pressure warning computer.
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or higher.
Page 695 of 825

694
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
The tire pressure warning system may become inoperative in the following condi-
tions:
(When the condition becomes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies are nearby.
●If a radio set at similar frequencies is in use in the vehicle.
●If a window tint that affects the radio wave signals is installed.
●If there is a lot of snow or ice on the vehicle, in particular around the wheels or
wheel housings.
●If non-genuine Lexus wheels are used. (Even if you use genuine Lexus wheels,
the tire pressure warning system may no t work properly with some types of
tires.)
●If tire chains are used.
●If the spare tire is in a location subj ect to poor radio wave signal reception.
● If a large metallic object which can interfere with signal reception is put in the
luggage compartment.
■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 switch is turned to the “ON” position, have it checked by your
Lexus dealer.
■After changing the engine oil (U.S.A. only)
Make sure to reset the oil maintenance data. ( P. 6 1 3 )
Page 696 of 825

5
When trouble arises
695
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
CAUTION
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Lexus dealer. The
vehicle will become extremely unstable during braking, and the ABS system may
fail, which could cause an accident resulting in death or serious injury.
■When the power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, hold firmly and
operate using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precaution s. 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.
Page 697 of 825

696
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold
and inflated to the inflation pressure re commended by the vehicle manufacturer on
the vehicle placard or tire inflation pressu re label (tire and load information label).
(If your vehicle has tires of a different size than the size indicated on the vehicle
placard or tire inflation pressure label [tire and load information label], you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure
monitoring system (TPMS-tire pressure warning system) that illuminates a low tire
pressure telltale (tire pressure warning light) when one or more of your tires is sig-
nificantly under-inflated. Accordingly, when the low tire pressure telltale (tire pres-
sure warning light) illuminates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for
proper tire maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger illumination of
the TPMS low tire pressure telltale (tire pressure warning light).
Page 698 of 825

5
When trouble arises
697
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
CAUTION
■Maintenance of the tires
Your vehicle has also been equipped with a TPMS (tire pressure warning system)
malfunction indicator to indicate when th e system is not operating properly. The
TPMS (tire pressure warning system) malf unction indicator is combined with the
low tire pressure telltale (tire pressure warning light). When the system detects a
malfunction, the telltale will flash for approximately one minute and then remain
continuously illuminated. This sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists . When the malfunction indicator is illumi-
nated, the system may not be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfunctions may occur for a variety of rea-
sons, including the installation of replacem ent or alternate tires or wheels on the
vehicle that prevent the TPMS (tire pressure warning system) from functioning
properly. Always check the TPMS (tire pressure warning system) malfunction tell-
tale after replacing one or more tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow the TPMS (tire pressure warning
system) to continue to function properly.
NOTICE
■Precaution when insta lling a different tire
When a tire of a different specification or maker is installed, the tire pressure warn-
ing system may not operate properly.
Page 699 of 825
698
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60E69U)
If a warning message is displayed
If a warning is shown on the instrument cluster, stay calm and perform the
following actions:
Master warning light
The master warning light also
comes on or flashes in order to
indicate that a message is cur-
rently being displayed on the
instrument cluster.
Multi-information display
Rear height control air sus-
pension display
If any of the warning lights comes on again after the following actions
have been performed, contact your Lexus dealer.