"The investigation is concluded", Henrich said Friday in Cologne, where Germany's fleet of government planes is based.
In October, Finance Minister Olaf Scholz had to take a commercial flight home from a summit in Bali, Indonesia after rats had chewed through cables of the Konrad Adenauer, disabling the aircraft for days.
Merkel planned to meet with Trump, President Xi Jinping of China and Argentine President Maruricio Macri.
Merkel also said she met with Russian President Vladimir Putin and underscored her concern about recent events in the Kerch Strait, cite of a naval standoff between Russia and Ukraine, adding that all escalation should be avoided.
The aircraft lost communications for almost an hour, forcing it to make an emergency landing in Germany's Cologne-Bonn airport.
After 30 minutes on board as firemen inspected the plane, a spokesman told reporters the replacement plane would be unable to fly to Buenos Aires, because the crew had already worked too many hours.
The plane had suffered a complete breakdown of the on-board communication system, a problem described as extremely rare, which forced the pilot to communicate via a satellite phone instead. She is unlikely to arrive until Friday evening and it was not immediately clear which meetings would have to be rescheduled.
It's not the first time German officials were left stranded. Last year, Merkel was delayed on a trip to Egypt because a windshield heater malfunctioned. Back then, the issue involved damage caused by rodents, German media outlets reported.