warning Lexus GS450h 2007 Using the audio system / LEXUS 2007 GS450H THROUGH JUNE 2006 PROD. (OM30727U) Service Manual

383
4-3. Do-it-yourself maintenance
4
Maintenance and care
CAUTION
■When inspecting or replacing tires
Observe the following precautions to prevent accidents. Failure to do so may cause
damage to parts of the drive train, as well as dangerous handling characteristics,
which may lead to fatal or injury accidents.
●Do not mix tires of different makes, models, tread patterns or tread wear.
●Do not use tire sizes other than those recommended by Lexus.
●Do not mix radial, bias-belted, or bias-ply tires.
●Do not mix summer, all season and winter tires.
■When initializing the tire pressure warning system
Do not push the reset switch without first ad justing the tire inflation pressure to the
specified level. Otherwise, the tire pressure warning light may not come on even if
the tire inflation pressure is low, or it may come on when the tire inflation pressure is
actually normal.
NOTICE
■Repairing or replacing tires, wheels and tire pressure warning valves and trans-
mitters
●When removing or fitting the wheels, tires or the tire pressure warning valve and
transmitter, contact your Lexus dealer as the tire pressure warning valve and
transmitter may be damaged if not handled correctly.
●When replacing tires, make sure also to replace the tire pressure warning valve
and transmitter grommets.
■Do not use puncture sealant sprays to repair flats
Puncture sealant sprays may damage tire pressure tire pressure warning valves and
transmitters.

389
4-3. Do-it-yourself maintenance
4
Maintenance and care
Wheels
■When replacing wheels
The wheels of your Lexus are equipped with tire pressure warning valves and trans-
mitters that allow the tire pressure warning system to provide advanced warning in
th
e event of a loss in tire inflation pressu re. Whenever wheels are replaced, the tire
pressure warning valves and transmitters must be switched over from the old
wheels. ( P. 3 76 )
If a wheel is bent, cracked or heavily corroded, it should be replaced. 
Otherwise, the tire may separate from
the wheel or cause loss of handling
control.
■ Wheel selection
When replacing wheels, care should be taken to ensure that they
ar

e equivalent to those removed in load capacity, diameter, rim
width, and offset.
Replacement wheels are available at your Lexus dealer.
Lexus does not recommend using:
• Wheels of different sizes or types
• Used wheels
• Bent wheels that have been straightened
• Lexus wheels with after market chrome plating
■ Aluminum wheel pr
ecautions
● Use only L
exus wheel nuts and wr enches designed for use with
your aluminum wheels.
● When r
otating, repairing or changi ng your tires, check that the
wheel nuts are still tight after driving 1000 miles (1600 km).
● Be car
eful not to damage the aluminum wheels when using tire
chains.
● Use only L
exus genuine balance weights or equivalent and a
plastic or rubber hammer when balancing your wheels.

390
4-3. Do-it-yourself maintenance
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in the
Owner’s Manual, as this may result in loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a tubeless tire.
Doing so may result in an accident, causing death or serious injury.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warning valves
and transmitters, make sure to have tires serviced by your Lexus dealer or other
qualified service shop. In addition, make sure to purchase your tire pressure
warning valves and transmitters at your Lexus dealer.
●Ensure that only genuine Lexus wheels are used on your vehicle. 
Tire pressure warning valves and transmitters may not work properly with non-
genuine wheels.

406
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

When trouble arises5
419
5-1. Essential information ........... 420If your vehicle needs to be 
towed........................................... 420
If you think something is 
wrong .......................................... 427
Event data recorder ................. 428 5-2. Steps to take in an

emergency............................ 430
If a warning light turns on or a 
warning buzzer sounds............ 430
If a warning message is 
displayed.................................... 436
If you have a flat tire 
(Vehicles with run-flat 
tires) ............................................. 455
If you have a flat tire 
(Vehicles with standard 
tires) ............................................. 456
If the hybrid system will not 
start .............................................. 466
If the shift lever cannot be 
shifted from P........................... 467
If you lose your keys ................. 468
When the electronic key  battery is discharged ............ 469
If the 12 volt battery is 
discharged .................................. 471
If your vehicle overheats ........ 475
If the vehicle becomes 
stuck ............................................ 478

430
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 vehicl e in a safe place and contact your Lexus
dealer.
*: Parking brake engaged warning buzzer:
 P. 4 4 4
Warning lightWarning light/Details
(U.S.A.)

(Canada)
Brake system warning light (warning buzzer)*
•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.
Calmly perform the following actions if any of the warning lights turn on or
flash. If a light turns on or flashes, bu t then turns off, this does not necessar
-
ily indicate a malfunction in the system.

5
When trouble arises
431
5-2. Steps to take in an emergency
Stop the vehicle immediately.
The following warning indicates the possibility of damage to the vehicle
that may lead to an ac cident. Immediately stop the vehicle in a safe place
and contact your Lexus dealer.
Have the vehicle inspected by your Lexus dealer immediately.
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.
Warning lightWarning light/Details
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
while the hybrid system is running.
Warning lightWarning light/Details
(U.S.A.)

(Canada)
Malfunction indicator lampMalfunction in:
• The hybrid system;
• The electronic engine control system;
• The electronic throttle control system; or
• The transmission control system.
SRS warning light
Malfunction in:
• The SRS airbag system; or
• The seat belt pretensioner system.

432
5-2. Steps to take in an emergency
*1: Electronically Controlled Brake System
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/Details
(U.S.A.)

(Canada)
ABS warning lightMalfunction in:
•The ABS; or
• The brake assist system.
ECB*1/VSC warning light
Malfunction in:
• The electronically controlled brake system; or
• The VSC.
Electric power steering system warning light Malfunction in the EPS.
Pre-collision system warning light (if equipped)Malfunction in the pre-collision system.
Warning lightWarning light/DetailsCorrection procedure
Open door warning light 
(warning buzzer)
*2
A door or a 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.

5
When trouble arises
433
5-2. Steps to take in an emergency
*2: Open door warning buzzer:
P. 4 4 3
*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
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 stays on after
blinking for 1 minute:
Malfunction in the tire pres-
sure warning system.
Have the system checked by
your Lexus dealer.
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.

434
5-2. Steps to take in an emergency
■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
a
s 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.
■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 seat belt buckle switches
●The driver's seat position sensor
●The inflators
●The warning light
●The interconnecting wiring and power sources