Instrument has a light flashing outside Los Angeles (9)
I believe the answer is:
astrolabe
'instrument' is the definition.
(astronomical instrument)
'a light flashing outside los angeles' is the wordplay.
'light flashing' becomes 'strobe' (light that flashes).
'outside' is an insertion indicator.
'los angeles' becomes 'LA' (abbreviation).
'strobe' enclosing 'la' is 'strolabe'.
'a'+'strolabe'='ASTROLABE'
'has' acts as a link.
(Other definitions for astrolabe that I've seen before include "Observational device" , "Old navigation instrument" , "Navigational device" , "Navigation aid" , "Early astronomical instrument" .)