One's fixed on banger maybe left on dish (1-5)
I believe the answer is:
l-plate
'one's fixed on banger maybe' is the definition.
('banger' can mean a car)
'left on dish' is the wordplay.
'left' becomes 'L' (common abbreviation).
'on' means one lot of letters go next to another.
'dish' becomes 'plate' (plate is a kind of dish).
'l'+'plate'='L-PLATE'
(Other definitions for l-plate that I've seen before include "Trainee-driver sign" , "Sign of driver under tuition" , "Sign of a learner driver" , "Learner drivers must display this" , "Learner driver's sign" .)