nonfunctional vs malfunctioning

nonfunctional and malfunctioning both are adjectives.

Word	Noun	Adjective	Verb	Adverb
nonfunctional	No	Yes	No	No
malfunctioning	No	Yes	No	No

As adjectives, nonfunctional and malfunctioning are synonyms defined as:

nonfunctional and malfunctioning: not performing or able to perform its regular function

nonfunctional (adjective)	malfunctioning (adjective)
not having or performing a function	not performing or able to perform its regular function
not performing or able to perform its regular function