Otago capped their resurgence at the end of the first half when a seemingly innocuous Hayden Parker kick bounced awkwardly for Daniel Hawkins, allowing Parker to hack the ball ahead and win the chase.
Poor discipline allowed Hawkins' boot to put Northland back in front after the break, and then the game swung again when Hawkins' own misdeeds saw him yellow carded after tackling Fa'asiu Fuatai in the air.
The loss of their pivot seemed to fire the Taniwhas into action as they dominated territory with 14 men and added five points to their tally through prop Ross Wright.
Ram was rewarded for being in the right place at the right time again by snaring an offload from Jone Macilai-Tori to pick up his second try.
The Northland forwards relished playing under the roof at Forsyth Barr, and their strong running with ball in hand gave Otago no chance of a comeback.
Otago eventually cracked under the pressure as Matt Moulds slid in under the posts to top off a strong performance for the Taniwha pack.
Otago will have to put this game behind them as they head north to take on Hawke's Bay for the Ranfurly Shield on Sunday.
Otago 23 (Franklin, Parker tries, Parker 2 pen, 2 cons, Breen pen)
Northland 40 (Waa, Ram 2, Wright, Moulds tries, Hawkins 3 con, 3 pen)
HT: 20-15