A new module was deployed in administration (or OSGI console) --> modules, after that, the modules page was not accessible.
The deployment was inconsistent an exception was thrown:
2016-10-07 16:13:30,735: ERROR [WebContainer : 15] org.jahia.services.render.filter.RenderChain:
Error while rendering the resource: Resource{node=/modules/serverSettings/7.1.3/templates/server-settings-base/system-components/manageModules/pagecontent/manage-modules,
primaryNodeTypeName='jnt:serverSettingsManageModules', templateType='html', template='default', configuration='module'} -> org.jahia.services.render.RenderException:
Redeploy the modules ( by flushing the content of the bundle-deployed folder and restart the server)