2007 Lexus GS450h tire pressure

414
4-3. Do-it-yourself maintenance
■Passenger’s side instrument panel
FuseAmpereCircuit
1ECU-IG RH10
Electric tilt and telescopic steering,
combination switch, power seat,
smart access system with push-but-
ton start, air conditioning system,
touch screen, shift lock system, tire
pressure warning system, front/rear
stabilizer system
2FR S/HTR RH15Seat heaters, seat heaters and venti-
lators
3RH-IG7. 5
Front right door control system, rear
right door control system, seat belt
pretensioners, transmission, seat
heaters, seat heaters and ventilators
4AM215Starting system
5FR DOOR RH20Front right door control system
6RR DOOR RH20Rear right door control system
7AIR SUS20AV S
8PWR OUTLET15Po w e r o u t l e t
9CIG15Cigarette lighter

440
5-2. Steps to take in an emergency
Have the malfunction repaired immediately.After taking the specified steps to correct the suspected problem, check
that the warning light turns off.
Warning lightWarning light/DetailsCorrection procedure
Open door warning light 
(warning buzzer)
*2
A door or the trunk is not
fully closed.
Check that all doors and the
trunk are closed.
Low fuel level warning light Remaining fuel 
(Approximately 2.6 gal. [10
L, 2.2 Imp.gal.] or less)
Refuel the vehicle.
Driver’s seat belt reminder
light (warning buzzer)
*3
Warns the driver to fasten
his/her seat belt.Fasten the seat belt.
Front passenger’s seat belt
reminder light
(warning buzzer)
*3
Warns the front passenger to
fasten his/her seat belt.
Fasten the seat belt.
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.

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.

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.

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.

452
5-2. Steps to take in an emergency
Wa r n i n g m e s s a g eDetailsCorrection procedure

Low tire inflation pres-
sure.Check the tire inflation
pressure, and adjust to the
appropriate level.
(Flashing)
(If equipped)The PCS is not currently
functional.
Clean the grille and the
sensor. This message appears
when the pre-collision
system is hot. In this case,
wait until the system
cools down.
(If equipped)
Intuitive parking assist is
dirty or covered with ice.
(The illustration shows
something on the left
front sensor.)
Clean the sensor.
(Flashing) 
(If equipped)
The radar cruise control
sensor is dirty or covered
with ice.
Clean the sensor.

5
When trouble arises
455
5-2. Steps to take in an emergency
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 pressure 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 an d 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).
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.