Jozy Altidore scored in the first half and Michael Bradley provided two assists as Klinsmann fielded a lineup mixing World Cup veterans with four players making their debuts.
Iceland scored in the 13th minute when a shot by Steindorsson, who played 21 games for Columbus last season, deflected off Orozco and caught Robles diving the wrong way.
The USA evened it up seven minutes later when Gyasi Zardes set up Bradley for a nice pass through to Altidore. The veteran striker finished for his 32nd career goal, just two behind Eric Wynalda for third place in American history.
Early in the second half, Sigurdarson showed impressive skill in curling a long shot past Robles. The Americans evened it off a set piece, with Orozco, another late addition to the U.S. roster, finishing work by Altidore and Birnbaum.
Steve Birnbaum then headed home the winning goal from Michael Bradley’s corner in the 90th minute.
The US have another friendly at StubHub Center against Canada on Friday night and it will be interesting to see what changes Klinsmann makes based on this performance.
USA 2016 Matches
March 29: USA v Guatemala – World Cup Qualifier – Buy USA v Guatemala Tickets