Status messages generated by Configmgr Components report its activity and problems when occurs .These status messages are primarily used to indicate the health of Configmgr 2012 Components .
While ago, John Nelson posted blog about ,Status Messages Documentation for Configmgr 2007 SP2 available here but after that ,haven't found any status message documentation for Configuration manager 2012.
There was a discussion recently on the Configmgr forum email list about status message document for CM12 R2 CU3 and Sherry Kissinger share the documentation to the group which am posting it here for rest of the world.
Saud from Microsoft posted PowerShell script that will help you to extract these status messages out of box using Configmgr 2012 SDK ,read the post on http://blogs.technet.com/b/saudm/archive/2015/01/20/enumerating-status-message-strings-in-powershell.aspx
This will help you to troubleshoot CM12 R2 CU3 Site Components and understand how Configmgr 2012 works .
Download the spreadsheet from TechNet Gallary.