private ["_veh","_action"];

if(count _this == 2) then
{
    _veh = _this select 0;
    _action = _this select 1;
} else
{
    _veh = _this select 3 select 0;
    _action = _this select 2;
};

_target = _veh getVariable "cargo";

if (isNull(_target)) exitWith {};
detach _target;
_veh setVariable["active", 0];
_veh setVariable["cargo", objNull];
_veh removeAction _action;