Overdrive Control Function
WARNING: This page is about a different car, the 2002 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.
During cruise control driving, the overdrive may be cut on an uphill grade. After the overdrive is cut, if the vehicle speed reaches the overdrive resume speed (set speed minus 1.2 mph, 2 km/h), and if the system determines that the uphill grade has finished, the overdrive will resume after overdrive resume timer operation. However, if the actual vehicle speed becomes slower than the overdrive resume speed before the timer operation has finished, the timer will be reset, and will start again when the vehicle speed reaches the overdrive resume speed.