[Gii]

pawn Код:

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys){
    if ( newkeys == KEY_DOWN && IsPlayerInAnyVehicle(playerid) ) {
        PlayerPlaySound(playerid, 1147, 0.0, 0.0, 0.0);
    }
    return true;
}

Caso queira especificar os veнculos.

pawn Код:

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys){
    if ( newkeys == KEY_DOWN && GetPlayerVehicleID(playerid) == 515 || GetPlayerVehicleID(playerid) == 514 ) {
        PlayerPlaySound(playerid, 1147, 0, 0, 0);
    }
    return true;
}