The 2011 runner-up Argentines will host Croatia in a quarterfinal in April.
Argentina clinched the tie with a doubles win by former Wimbledon runner-up David Nalbandian and Eduardo Schwank here on Saturday, which gave the visitors an insurmountable 3-0 lead. Nalbandian and Schwank fought back from a two- sets-to-love deficit against oft-injured former world No. 2 Tommy Haas and Philipp Petzschner in order to prevail.
In Sunday's meaningless reverse singles, Juan Ignacio Chela gave Argentina a 4-0 advantage by besting Florian Mayer 7-5, 7-5 and the Germans finally got a point when Cedrik-Marcel Stebe downed Schwank 7-6 (7-1), 7-5 on the red clay at Stechert Arena Bamberg.
In Friday's opening singles, Juan Monaco and Nalbandian posted big wins for the visitors.
Argentina is still trying for that elusive first Davis Cup title, having finished as the runner-up four times. The Argentines lost to Spain in last year's finale in Seville.
Three-time champion Germany is 2-6 all-time against Argentina, including a 5-0 setback in their last meeting back in 2003.