If you are using SSL, you may need to check the following note, or check it anyways:
12.2 E-Business Suite Applications Manager Non SSL HTTP URL Displayed When Selecting Self Service / HTML OAM Client Links (Like Workflow Or License Manager) Causing 'Page Not Found' Errors (Doc ID 2257838.1)
Thank you Michael. I tried setting Weblogic Plug-in being checked and bounce the oacore but the issue did not fix. Links like Workflow or License Manager under OAM are working fine. Only the Weblogic Console and FMW Control link under Site map are not giving http:// in the URL.