Medal of Honor: Vanguard Cheats - PlayStation 2

Cheat Codes
Press [Plus] during game play. Then press [Up], [Down], [Up]. [Down]. The message "Enter cheat code" will appear at the top left. Then, enter one of the following codes to activate the corresponding cheat function:

[Up], [Right], [Left], [Down], [Down], [Up] - Invisibility
[Right], [Left], [Right], [Down], [Up], [Right] - Extra armor
[Right], [Left], [Right], [Down], [Up], [Right] - Decrease enemy accuracy

Shoot twice without reloading
This only works with the K98 German rifle. Go to the iron sights and fire, then quickly go out and fire again. You will have only moved the bolt once.

Glitch: Quick reloads
To bypass the long reload times, press Melee while reloading. The game will give you a full clip just as if you just reloaded.

Unlock Medals
Complete the indicated task to unlock the corresponding medal in your Service Record:

Campaign Medal - Complete all levels in Campaign mode.
Bronze Stars - Complete a mission without dying. Note - A Sprint Recovery bonus is acquired with each Bronze Star earned.
Silver Stars - Complete Campaign mode without dying. A Health Recovery bonus is acquired with each Silver Star earned.
Oak Leaves - Earn any seven medals in Campaign mode. A Health Bonus is acquired with each Oak Leaf earned. 
Wings - Land in designated drop zones.
Weapon Expert - Use each available weapons during a mission.
Marksman Award - Shoot a specific number of people in the head during a mission.
World War II - Earn all of the medals in Campaign mode.
Victory Medal - Unknown.