The U.S. dominated possession and had some good opportunities but were unable to finish against the stout Ecuadorian defence until the centre forward's first international goal since the Copa America quarter-final against Ecuador in 2016 broke the deadlock.
Berhalter, a former national team defender who played at two World Cups, took over from interim head coach Dave Sarachan in December after five seasons with Major League Soccer side Columbus Crew.
(Reporting by Rory Carroll; Editing by Greg Stutchbury)