Select "Options" at the main menu. Hold R2 and quickly press Up(2), Down(2), Left, Right, Left, Right, Square, Circle, Square, Circle at the options menu. The Cheat Name screen will appear to confirm correct code entry. Enter one of the following case-sensitive codes then press X to exit back to the options screen. You can now continue your game and see the effects of the cheat.
Note: codes are case-sensitive
TopBird - Cannot get knocked off
Hobble - Hard tracks with normal AI settings
PMeterGo - Maximum performance meter
Passport - All courses
AllChar - All characters
LaPinata - All wetsuits
AllOutAI - Expert AI
Festival - All ending FMV sequences
IBelieve - Play Time Trials against a UFO
F18 - Play Time Trials against a miniature F-18 jet
SEADOO - Play Time Trials against ghost of currently selected player
Successfully complete the game under the hard difficulty setting to unlock Steve as a playable character and the Bermuda Triangle level.
Collect 100 balloons in countdown mode.
Loch Ness: See monster:
You can see the Loch Ness monster by turning right off the track immediately at the very start in freestyle mode. If you go out far enough, the monster will take you under and blast you back onto the track.
Play the track in career mode. When you reach the waterfall, hold down the nose of your jet ski so that you submerge. You will pop up in a cave on the other side of the waterfall. Once you reach the start of the course on the next lap, the Loch Ness monster will be waiting there.
How to unlock Steve and the Burmuda Triangle level
Just simply complete the game on hard mode and you will unlock Steve (stats maxed out) and the Burmuda Triangle level.