[JaTochNietDan]

You have an additional bracket there.

pawn Код:

public OnPlayerExitVehicle(playerid, vehicleid)
{
    if(!IsPlayerInVehicle(playerid,415) && gTeam[playerid] == TEAM_UNDERCOVER)
    {
        SetPlayerColor(playerid,COLOR_BLUE);
    }
    return 1;
}

Also it's worth noting that IsPlayerInVehicle checks if the player is in vehicleid 415, not if he is in a vehicle that has the model ID of 415.