Mechanical failure — analysis (9)
I believe the answer is:
breakdown
I believe this is a double definition.
'mechanical failure' is the first definition.
(I've seen this before)
'analysis' is the second definition.
(breakdown is a kind of analysis)
(Other definitions for breakdown that I've seen before include "sudden failure to work" , "Collapse - analysis" , "Problem with car" , "Detailed analysis" , "As result of mental stress" .)