2004 Lexus SC 430 Owners Manual - Page 239

STARTING AND DRIVING TIRE PRESSURE WARNING SYSTEM If you drive over about 180 km/h (112 mph) with the tires not inflated at the designated pressure for high speed driving, the warning light may turn on. If the tires are at the designated pressure for ordinary speed driving, decreasing the speed will turn off the warning light. (For the designated pressure for high speed driving, see "Specifications" on page 326.) This 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, adjusting the tire inflation pressure will turn off the warning light. For details about adjusting the tire inflation pressure, see "Checking tire inflation pressure" on page 329. Vehicles with run-flat tires: If the warning light is on, the tire inflation pressure is lower than specified. Stop your vehicle at a safe place as soon as possible and check that the tire inflation pressure is as specified on the tire and loading information label. The tire pressure gauge is located in the tool bag. If the warning light comes on or blinks even after tire inflation pressure adjustment, it is probable that you have a flat tire. If you cannot verify the tire inflation pressure soon, go to the nearest Lexus dealer or authorized tire dealer at the moderate speed and do not ever exceed 90 km/h (55 mph) and have all your vehicle's tires checked and adjusted. And whether there is a flat tire or not should be also checked at this time. If any tire must be replaced, see "If you have a flat tire" on page 245. If the warning light does not go off about more than 15 minutes after air is put in the deflated tire, the system might be malfunctioning. Consult your Lexus dealer. 219 31sa02b This light and chimes warn you that the tire inflation pressure is low. This light comes on when the ignition switch is turned to the "ON" position and goes off after a few seconds. This means the low tire pressure warning light is operating properly. If the warning light does not go off, or comes on or blinks during driving, or the chimes sound, this indicates that tire inflation pressure is low. Make sure there is no flat tire. If the warning light comes on again even after air is put in the tires, a tire may be flat or the system may be malfunctioning. If this warning light comes on, the action you must take is different depending on the type of tires used.