Signature 5748-0 is a meta engine signature.
Definition of Meta signature is here
http://www.cisco.com/univercd/cc/td/doc/product/iaabu/csids/csids13/idmguide/dmsigeng.htm#wp1040063
5748-0 should fire after detecting traffic that matches the sequence of the subsigs 1-5 as defined in 5748-0.
Subsigs 1-5 are meta component signatures, and by default configured to have no event action of their on, and should be left that way. This is because they are only looking for a very small subset of the main meta signature, and on their own could generate a lot of event alerts if set to produce alert.
If you have changed the default action, you should revert them back to default.
Depending on whether the event log storage has wrapped, you would be able to use the IDM for 5.x or SDM for 6.x using >monitoring>events to view if the signature has fired for the time setting you set.
I hope this information helps you.