Overdrive Function
WARNING: This page is about a different car, the 2002 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
The overdrive may be canceled if the vehicle travels on a upward slope during cruise control driving. After the overdrive is canceled, if the vehicle speed exceeds the overdrive return speed (set speed: 1.2 mph, 2 km/h) and it is determined that the slope has finished, the vehicle returns to overdrive mode again.