I changed a lookup value and ran the package.But the package picked up the old value when it ran.Do I need to refresh something after making any mapping change?
Are you sure it is a package? Because packages don't need to be refresh.But if it is a scenario then you must regenerate the package or create a new scenario.
bit confusing to answer this:
However a generic answer is : Mappings are usually done in the interfaces, now if you have changed the mapping in the interface and saved it, and now you are using the same interface in the package without creating the scenario of either of them, then there is no need of any refresh.
How ever if the case is:
Interface also has a scenario and Package also has a scenario , then you have regerate both the scenarios and then execute it. All the changes done by you will be reflected then.