Instructions
Start or continue a Career Mode game from the main menu. It's not necessary to start a new game in order to use the cheat. But its use will be recorded in your profile. As a result, you may want to create a new profile and start from scratch. This will allow you to keep one profile clean, and keep another for using all the cheats you like.
Enter free-roam mode in your chosen "cheat" career profile. You can access the cheat code menu at any time other than during a race. Press the "Start" button to pause the game and access the menu. Select "Options" from the pause menu.
Select "Secret Codes" from within the "Options" menu, and enter one of the following codes: $EDSOC will award $10,000, S1D3K1CK and BIGMONEY will award $15,000 each. They can be entered as many times as you like, until you have enough cash.