Complete every objective in single mission dossiers first hand, and you'll be able to use these. A sound will confirm entry. All of them must be done in the Cheats option when start is pressed during gameplay.

Press B(2), Y, X(2), A at the cheat menu.

X(2), A, B, A at the cheat menu. You will not be able to complete the game properly if the code is on. This code also doesn't require you to complete the game to use it.

A, X, B, Y, A at the cheat menu.

X(2), Y, A, B at the cheat menu.

B, A, X, Y, A at the cheat menu.

Y(2), B, X, A at the cheat menu.

A(2), X, B, Y at the cheat menu.

X, A, Y, B, X at the cheat menu.