2007 Lexus GS 450h User Guide - Page 395

4-3. Do-it-yourself maintenance n Selecting ID codes When replacing tires, make sure to select the ID code set that matches the new tire set. If the incorrect ID code is selected, the tire pressure warning system will not operate properly. After a certain period of time, the tire pressure warning light comes on after blinking for 1 minute to indicate a system malfunction. "MAIN" "2nd" n When to replace your vehicle's tires 4 Tires should be replaced if: Maintenance and care l You have tire damage such as cuts, splits, cracks deep enough to expose the fabric or 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 Tire life Any tire over 6 years old must be checked by a qualified technician even if they have seldom or never been used or damage is not obvious. n If the tread wears down below 0.16 in. (4 mm) on snow tires The effectiveness of snow tires is lost. n Low profile tires (245/40R18, P245/40R18 and 245/40ZR18 tires) Generally, low profile tires will wear more rapidly and tire grip performance will be reduced on snowy and/or icy roads when compared to standard tires. Be sure to use snow tires or snow chains on snowy and/or icy roads and drive carefully at a speed appropriate for road and weather conditions. 379