All Instant Action Levels: Up, Down, Left, Right, L1, R1, L1, R1 at the new game/continue screen.

X-Wing and Tie Fighter: Complete all campaign and challenge missions.

To enter cheats you must be on the New Game/Continue Screen.

Big Heads
right, up, left, down, right, up, left, down,right, L1, R1, L1 R1

All Eviroments
down, up, up, down, left, right, L1, R1, L1, R1

All Instant Action Levels
up,down,left,right,L1,R1,L1,R1

Unlimited Amunition
up,right,down,left,up,right,down,L1,R1

Invincibillity
up,down,left,right,left,left,right,right,L1,L1,R1,R1,L2,R2

All Plains and Missions
Triangle (3), Square (3), L1,R1,R2 (2), L2 (2)

You will hear a voice say Secret code accepted if you entered the cheat right.

Punch in on title screen

Invulnerability:
U,D,L,R,L,L,R,R,L1,L1,R1,R1,L2,R2

Infinite ammo:
U,R,D,L,U,R,D,L,L1,R1

On the menu with Continue and New Game, enter RIGHT, UP, LEFT, DOWN, RIGHT, UP, LEFT, DOWN, RIGHT, L1, R1, L1, R1.

On the menu with Continue and New Game, enter UP, DOWN, LEFT, RIGHT, LEFT, LEFT, RIGHT, RIGHT, L1, L1, R1, R1, L2, R2.