Go to the "Garage" screen in scenario mode and press Up(2), Down(2), Left, Right, Left, Right, Select.
Pause the game, press Select, then unpause the game. Now your car will be controlled by the CPU. Repeat this code to return to normal control.
Full character attributes
Go to the "Garage" screen in scenario mode and press Down(2), Up(2), Right, Left, Right, Left, Select.
More Cheats, Achievements
