2012 Lexus IS 350 User Guide - Page 199

2-4. Using other driving systems Selecting conventional constant speed control mode Constant speed control mode differs from vehicle-to-vehicle distance control mode. When constant speed control mode is selected, your vehicle will maintain a set speed regardless of whether or not there are other vehicles in the lane ahead. Press the "ON-OFF" button to activate the cruise control. Cruise control indicator will come on. Press the button again to deactivate the cruise control. Switch to constant speed control mode. (Push the lever forward and hold for approximately one second.) When in constant speed control mode, to return to vehicle-to-vehicle distance control mode, push the lever forward again and hold for approximately 1 second. After the desired speed has been set, it is not possible to return to vehicle-to-vehicle distance control mode. If the "ENGINE START STOP" switch is turned off and then turned to IGNITION ON mode again, the vehicle will automatically return to vehicle-to-vehicle distance control mode. 206