Lexus 2003 SC430 Owner's Manual page 237

STARTING AND DRIVING
NOTICE
D Do not use liquid sealants for a flat tire as air pressure
sensors will be damaged.
D Take due care not to go over a curb stone and be
careful of the holes in the road because deflated tire
pressure affects tire cushion performance.
wheels, tires, body,
components could be damaged.
D Your ground clearance is reduced if the run–flat tire
goes flat so avoid driving over obstacles and drive
slowly on rough, unpaved roads and speed bumps.
Also, do not attempt to go through an automatic car
wash as the vehicle may get caught, resulting in
damage.
D When the tires must be replaced, have them replaced
by the nearest Lexus dealer or authorized tire dealer.
The tire pressure sensor will be affected by the
installation or removal of tires.
D When the tires must be replaced, replace the
grommets for air pressure sensors as well.
220
The
suspension and other
Vehicles with standard tires:
If the warning light is on, the tire pressure is lower than
specified.
Stop your vehicle at a safe place as soon as possible and
check that the tire pressure is as specified on the tire pressure
label. The air pressure gauge is located in the tool bag. If the
warning light comes on or blinks even after tire pressure
adjustment, it is probable that you may be a flat tire. If the tire
goes flat, change to the spare tire. (See page 241).
The spare tire is not equipped with the tire pressure sensor.
So, the warning light remains on even if the spare tire is
mounted.
If the warning light does not go off more than 15 minutes after
air is put in the deflated tire, the system might be
malfunctioning. Consult your Lexus dealer.
CAUTION
If the warning light comes on, observe the following
instructions:
D Decelerate as soon as possible to the most
appropriate speed that conditions permit.
D Avoid abrupt steering wheel maneuvering and
braking. If the vehicle tires deteriorate, you could
lose control of the steering wheel or the brakes,
causing death or serious injury.