2010 Lexus RX 450h User Guide 2 - Page 494

4-3. Do-it-yourself maintenance Registering ID codes The tire pressure warning valve and transmitter is equipped with a unique ID code. When replacing a tire pressure warning valve and transmitter, it is necessary to register the ID code. Have the ID code registered by your Lexus dealer. n When to replace your vehicle's tires Tires should be replaced if: l You have tire damage such as cuts, splits, cracks deep enough to expose the fabric, and bulges indicating internal damage. l A tire goes flat repeatedly or cannot be properly repaired due to the size or location of a cut or other damage. If you are not sure, consult with your Lexus dealer. n Replacing tires and wheels If the ID code of the tire pressure warning valve and transmitter is not registered, the tire pressure warning system will not work properly. After driving for about 20 minutes, the tire pressure warning light flashes for 1 minute and stays on to indicate a system malfunction. n Tire life 4 Maintenance and care Any tire over 6 years old must be checked by a qualified technician even if it has seldom or never been used or damage is not obvious. n If the tread on snow tires wears down below 0.16 in. (4 mm) The effectiveness of the tires as snow tires is lost. 499