While not AR codes, these button combinations are standard cheats already built into the game:
04153D4C 60000000
(M) FURQ-8RGY-8UT27. 9CV0-TEJ2-BXV7Z. Nitro Never Decreases. UCYV-A080-Z3P65. UEJ9-6P7Z-V4PKC. Speedbreaker Never Decreases. UGAE- Codejunkies nfs most wanted gamecube ar codes
Remember, using cheats can sometimes lead to unexpected glitches, so it's always a good idea to save your game before activating a new code. While not AR codes, these button combinations are