The following are known Code Breaker Codes for High Heat Major League Baseball 2003 on Nintendo Game Boy Advance (GBA).

These codes are for the U.S. version of the game.

• Master Code – Must Be On
  94038ECE 383E
  D5D1BBF8 0958
  2C2B9416 DD85
• Infinite Balls
  5352B77A 5D48
• 1 Ball And You Walk
  D292BFCE 4D78
  554B9373 1940
• 2 Balls And You Walk
  D292BFCE 4D78
  5553B37B 1D48
• 3 Balls And You Walk
  D292BFCE 4D78
  534A9772 5940
• Infinite Outs
  62F2BE7A 5D0D
• 1 Out And You Are Out
  E332B6CE 4D3D
  64F3BA7B 1D0D
• 2 Outs And You Are Out
  E332B6CE 4D3D
  62EA9E72 5905
• Infinite Strikes
  9B16A7AA E5E8
• 1 Strike And You Are Out
  1AD6AF1E F5D8
  9D17A3AB A5E8
• 2 Strikes And You Are Out
  1AD6AF1E F5D8
  9B0E87A2 E1E0
• Team 1 Scores 150
  ACB56C8D E5F9
• Team 1 Scores 0
  1AF0AA5C 159C
• Team 2 Scores 150
  AAB5688C A5F9
• Team 2 Scores 0
  1CF0AE5D 559C

Home Run Derby Codes

• P1 Has 150 Home Runs
  E55355B3 CD49
• P1 Has 0 Home Runs
  53169362 3D2C
• P2 Has 150 Home Runs
  D55355B3 CD0C
• P2 Has 0 Home Runs
  63169362 3D69
• P3 Has 150 Home Runs
  AD5345B3 C5C9
• P3 Has 0 Home Runs
  1B168362 35AC
• P4 Has 150 Home Runs
  9D5345B3 C58C
• P4 Has 0 Home Runs
  2B168362 35E9
• Press Select For P1 No Outs
  6212B54F 592D
  55519755 5D1E
• Press Select For P2 No Outs
  6212B54F 592D
• Press Select For P3 No Outs
  6212B54F 592D
  65519755 5D5B
• Press Select For P4 No Outs
  6212B54F 592D
  63519354 1D5B