1) Did sub-supplier process preparation has been done?
(Resource: Preparation schedule of sub-supplier)
2) Does supplier has finished audit for sub-supplier as their schedule?
3) Did supplier confirm the 2nd tier parts quality by receiving inspection, inspection method, frequency? (Actual check)
4) Did supplier approve sub-supplier's PPAP? (ex.Control plan) And does supplier confirm the result of sub-supplier action(Test report, inspection report, etc.,) for required items?