Level select:
Hold L1 and press Down, Up, Left(2), Circle, Right, Down, Square at the main menu.

Unlimited health:
Pause game play, then hold L1 and press Triangle, Square, Triangle, Square, Triangle, Circle, Triangle, Circle.

Unlimited rage:
Pause game play, then hold L1 and press Left, Down, Left, Down, Right, Up, Right, Up.

All weapons:
Hold L1 and press Square, Circle, Down, Left, Circle(2), Triangle at the main menu.

Unlimited ammunition:
Pause game play, then hold L1 and press Left, Circle, Right, Square, Up, Triangle, Down, X.

Daywalker difficulty setting:
Hold L1 and press Left, Circle, Up, Down, Square, Circle, X at the main menu.

Escorted NPCs are invincible:
Pause game play, then hold L1 and press Square, Circle, Triangle, X, Square, Circle, Triangle, X. This code can only be enabled in levels that you are escorting NPCs.