are you looking for a global list of all active timers?
I'm not sure but maybe the timers are listed for deployments (I never looked for that)
I think it will be worth to have such details, you might file a JIRA feature request for that.
take a look under deployment resources.
There should be some info about deployed timers under /deployment=<name-of-deployment>/subsystem=ejb3/service=timer-service/timer=<name-of-timer>
in case that you have ear deployment you should use /deployment=<name-of-deployment>/subdeployment=sub/....
you can find bunch of runtime deployment stuff under there each subsystem can expose some of their own stuff.