Cruise Control: Set
WARNING: This page is about a different car, the 1997 Lexus SC 300. However, it is still accessible from the selected car via links, so may be relevant.
Drive vehicle at speed less than 25 MPH. Try to set speed by moving lever downward. It should not be possible to set speed. Accelerate to speed greater than 25 MPH. Try to set desired speed. It should now be possible to set desired speed.