The 34-year-old was charged with driving with excess breath alcohol on Victoria Street in Petone on 15 July.
The 2011 World Cup star tweeted that he was due in Hutt Valley Distric Court this morning and would plead guilty.
He has since done so and was fined $600 and disqualified from driving for six months.
Weepu had initially fought for name suppression.
The former Hurricanes star played 73 tests for the All Blacks from 2004-2013.