Check temperature on car (5)
I believe the answer is:
audit
'check' is the definition.
(an audit is an examination or check)
'temperature on car' is the wordplay.
'temperature' becomes 't' (abbreviation).
'on' means one lot of letters go next to another.
'car' becomes 'audi' (Audi is a German car brand).
't' after 'audi' is 'AUDIT'.
(Other definitions for audit that I've seen before include "review of books" , "vetting of books" , "special ale" , "Financial review" , "Examine accounts" .)