you need to set break points in your service and see if it is even being called. I would use an url relative to the root of the site ie /Services/ServiceModule.svc/Method not ../Services/ServiceModule.svc/Method
it also looks inconsistent, is it ServiceModule.svc or ModuleService.svc? you've listed it both ways.
you can also use firebug and see what is the status code returned from the ajax request.
Hope that helps,
Joe