Sega Rally Championship 2

All seasons:
Press Up, Left, Down, Right, B, A, B, Right, Down at the title screen. All tracks, including the Secret Rally track will be unlocked.

All cars:
Press Up, Down, Up, B, A, Left, B(2), Down at the title screen. Normally, the following must be done to unlock the twelve additional cars. There are an additional twelve cars that can be unlocked and controlled. Enter into "10 Year Championship" mode and finish first in every year. A new car is unlocked for each year with a first place finish. Note: Only one new car is unlocked per year; completing the same year multiple times in first place has no effect.

Two additional bonus cars are unlocked by playing in arcade mode. The Renault Maxi Megane is unlocked after finishing in seventh place or better under the "Easy" difficulty setting. For Toyota Corolla Tien, highlight the Toyota Corolla on the car selection screen, hold L, then select that car.
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Change frame rate:
Press Up, A, Down(2), Left, Right, B(2), Down at the main menu to change the frame rate to 60 per second. A sound will confirm correct code entry. Press Up, A, Down(2), Left, Right, B(2), Up at the main menu to change the frame rate to 30 per second.

Less detailed tracks:
Press Y or R when making a choice on the track or mode selection screen. The track will be less detailed and the race timer will appear on the right side of the screen while the game's display rate is increased.

Secret Rally track:
Finish in first place in every year under "10 Year Championship" mode.

Alternate car colors:
Press L when making a choice on the car selection screen.

Control replay camera:
Press A, Y, or X to change the replay view. Use the D-pad to rotate the camera angle. Press B to return to the normal replay angle. Press Down while in the driver's view to switch to a behind the car view.

Control car preview camera:
Use the D-pad to change the view of the cars at the car selection screen.

Hidden cone challenge:
Select arcade mode and begin game play in the Rivera race in either championship or practice. Drive as usual until reaching the last turn. Two red construction cones should appear as the turn is approached. Intentionally hit both of the cones. A sound with each hit will confirm this part of the trick. Turn around, and drive your car in the wrong direction. An opening to a hidden section of the track will eventually appear. Enter it to find a hidden section of track that contains many construction cones. The game will give you 29 seconds (separate from the normal race time) to knock down as many cones as possible for 100 points each.