The following guide is provided courtesy of Quality Management and Training of the UK. It provides an excellent overview of a variety of root cause analysis (RCA) techniques.
QM&T : Mini Guide to Root Cause Analysis
The 5-Whys
Understanding How to Use the 5-Whys for Root Cause Analysis
5-Whys Example – Hydraulic Leak
Fish-Bone Diagram
Fish-Bone Template – Excel File
Reference and Academia
“Do Learning Teams Make RCA Obsolete?” – Bob Latino, Relability Center