Complain about resistance one's seen on line (7)

I believe the answer is:

railcar

I'm a little stuck... Click here to teach me more about this clue!

'one's seen on line' is the definition.
I can't tell whether this defines the answer.

'complain about resistance' is the wordplay.
'complain' becomes 'rail' (railing is a kind of complaining).
'about' becomes 'ca' (circa).
'resistance' becomes 'r' (electronics abbreviation).
'rail'+'ca'+'r'='RAILCAR'

Can you help me to learn more?

(Other definitions for railcar that I've seen before include "Wagon on tracks" , "It's found on tracks" , "Small train" , "Powered train unit" , "vehicle on the line?" .)

I've seen this clue in The Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.