Caygill said initially, it would look at "wayfinding" and roadworks signs, or even welcome signs.
"The consultation would be asking effectively if people would be preferring to see haere mai or both."
Transport committee member and West Coast Regional Council chairman Allan Birchfield was sceptical.
"Just explain this: we're going to have roadwork signs in Māori?" he asked.
Caygill said that might happen, but it had not been settled. The stop-go signs used for roadworks would not be up for debate.
A lot of signs were photographic, without words. Where there were strong safety concerns NZTA saw no need to consult.
"The majority of the people in New Zealand don't speak Māori, so they'll have no bloody idea what [a sign] is trying to say," Birchfield said.
Committee member Peter Ewen said NZTA already had "some difficulty complying" with its own standards.
A "profusion" of signs at certain corners were a distraction for drivers, Ewen said.
Caygill said it was trying hard not to have more signs.
"That's not the point here, it's about what signs are where ... there will no doubt be interest."