Lexus GS450h 2007 Do-it-yourself maintenance / LEXUS 2007 GS450H FROM JULY 2006 PROD. OWNER'S MANUAL (OM30A05U)

5
When trouble arises
441
5-2. Steps to take in an emergency
*2: Open door warning buzzer:
P. 4 4 9
*3: Driver's and front passenger’s seat belt reminder buzzer:
The driver’s and front passenger’s seat belts reminder sounds to alert the driver
and front passenger that his or her seat belt is not fastened. The buzzer sounds
intermittently for 10 seconds after the ve hicle has reached a speed of at lest 12
mph (20 km/h). Then, if the seat belt is still unfastened, the buzzer will 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.
Take appropriate action in
accordance with the message
displayed on the multi-infor-
mation display.
■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.
■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.

442
5-2. Steps to take in an emergency
■SRS warning light
This warning light system monitors the following:
●The airbag sensor assembly
●Front airbag sensors
●The curtain shield airbag sensors
●The side and curtain shield airbag sensors
●The occupant detection sensor
●The front passenger occupant classification ECU
●“AIRBAG ON” and “AIRBAG OFF” indicator lights
●The pressure sensor
●The belt tension sensor
●The seat belt buckle switches
●The driver's seat position sensor
●The inflators
●The warning light
●The interconnecting wiring and power sources
■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 does not turn off the tire pressure warning light.
■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 caus ed by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the warning light.

5
When trouble arises
443
5-2. Steps to take in an emergency
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 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.
●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.

444
5-2. Steps to take in an emergency
If a warning message is displayed
Stop the vehicle immediately.A buzzer sounds and a warning message is shown on the multi-informa-
tion display. The following warnings indicate the possibility of damage to
the vehicle that may lead to an acci dent. Immediately stop the vehicle in a
safe place and contact your Lexus dealer.
Wa r n i n g m e s s a g eDetails
Malfunction in the hybrid system.
(Flashing)
Abnormal engine oil pressure.
The warning light may turn on if the engine oil pres-
sure is too low.
If a warning is shown on the multi-information display, stay calm and per-
form the following actions:
Multi-information display
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
multi-information display.
If any of the warning li ght turns on again after pe rforming the following
actions, contact your Lexus dealer.

5
When trouble arises
445
5-2. Steps to take in an emergency
Have the vehicle inspected by your Lexus dealer immediately.A buzzer sounds and a warning message is shown on the multi-informa-
tion display. 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.
Wa r n i n g m e s s a g eDetails
Malfunction in the automatic headlight leveling sys-
tem.
Malfunction in the rear lights system.
Malfunction in the tire pressure warning system.
The tire pressure warning light will blink for 1 minute
and then stay on.
(Flashing)
Malfunction in the steering lock system.

446
5-2. Steps to take in an emergency
Wa r n i n g m e s s a g eDetails
(If equipped)
Malfunction in the active stabilizer suspension sys-
tem.

(If equipped)Malfunction in the PCS.
(If equipped)
Intuitive parking assist malfunction. The malfunctioning sensor is shown flashing on the
display. (The illustration shows malfunctioning left
front sensor.)
(Flashing) 
(If equipped)
Malfunction in the radar cruise control system. Stop the vehicle in a safe place. Switch the power
switch to “OFF” and then to “IG-ON” mode again to
reset the cruise control system.

5
When trouble arises
447
5-2. Steps to take in an emergency
■If the tire pressure warning system is inoperative
The system will be disabled in the following conditions:
(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 more than 73 psi (500 kPa, 5.1 kgf/cm2 or bar).
The system may be disabled in the following conditions:
(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 the tire pressure warning select switch is set to a different tire setting.
●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.
●If tire chains are used.
■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 power switch is turned to “IG-ON” mode, have it checked by your Lexus
dealer.
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.

448
5-2. Steps to take in an emergency
Have the vehicle inspected by your Lexus dealer immediately.
Failing to investigate the cause of th e following warning may lead to the
system operating abnormally and possibly cause an accident. Have the
vehicle inspected by your Lexus dealer immediately.
*: Electronically Controlled Brake System
Wa r n i n g m e s s a g eDetails
Malfunction in the TRAC, VSC or hill-start assist con-
trol system.
In some cases, only “CHECK VSC” or “CHECK
ECB
*” is displayed.
(U.S.A)
(Canada)
Malfunction in the ABS or BA.In some cases, only “CHECK VSC” or “CHECK
ECB
*” is displayed.
Malfunction in the VGRS.
(Steering guide symbol
and arrows are flashing)
The steering sensor cable is broken and signals can-
not be received.

5
When trouble arises
449
5-2. Steps to take in an emergency
Have the malfunction repaired immediately.A buzzer sounds and a warning message is shown on the multi-informa-
tion display. After taking the spec ified steps to correct the suspected
problem, check that the warning message turns off.
Wa r n i n g m e s s a g eDetailsCorrection procedure
One or more of the doors
is not fully closed.
The system also indi-
cates which doors are
not fully closed.
flashes and a
buzzer sounds to indi-
cate that one or more of
the doors is not fully
closed (with the vehicle
having reached a speed
of 3 mph [5 km/h]).
Make sure that all of the
doors are closed.
The hood is not fully
closed.
flashes and a
buzzer sounds to indi-
cate that hood is not fully
closed (with the vehicle
having reached a speed
of 3 mph [5 km/h]).
Close the hood.

450
5-2. Steps to take in an emergency
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)
The moon roof is not fully
closed (with the power
switch “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 hybrid system has
overheated.Stop and check. 
( P. 4 8 0 )