Maybe try these:
Unable to update, always get INSTL_ERR12 - Ford / SYNC 3 Support - CyanLabs Official Community
I am getting Error Code: LST_ERR05 - Ford / SYNC 3 Support - CyanLabs Official Community
These are topics about this on the forum. This issue is usually due to a hardware failure.
Search results for ‘INSTL_ERR12 #ford’ - CyanLabs Official Community