Highlight the "Multiplayer" selection in the options menu, then hold L1 + R1 + R2 + Left and press X to display the cheat menu. Then, enter one of the following codes to activate the corresponding cheat function:

5-0 mode

Enter "BDK" as a code at the cheat menu.

Sidecar mode

Enter "CMB" as a code at the cheat menu.

Jailbreak mode

Enter "KLFSDA" as a code at the cheat menu.

Four nitros in Jailbreak mode

Enter "FDMFG" as a code at the cheat menu.