Select the "Extras" option at the main menu, then choose the "Enter Code" selection. Then, enter one of the following codes to activate the corresponding cheat function:
Enter "GIVEALL" as a code to unlock all tracks.
Enter "GIEVEPIX" as a code to unlock all cars and get one million credits.
Enter "GIVECASH" as a code.
Enter "RAIDERS" as a code to unlock the Big Rig.
Enter "WOTKINS" as a code to unlock the Flatmobile.
Enter "ELPUEBLO" as a code to unlock the El Diablo.
Enter "RUTTO" as a code to unlock the Pimpster.
Enter "KALJAKOPPA" as a code to unlock the Rocket.
Enter "GIEVCARPLZ" as a code to unlock the School Bus.
Win the indicated class' cup in the Grand Finals to unlock the corresponding car: